diversification within reduced fisheries portfolios signals...
TRANSCRIPT
Diversification within reduced fisheries portfolios
signals opportunities for adaptation among a coastal
Indigenous community
by
Sachiko Ouchi
B.Sc., University of British Columbia, 2016
Project Submitted in Partial Fulfillment of the
Requirements for the Degree of
Master of Resource Management
in the
School of Resource and Environmental Management
Faculty of Environment
Report No: 734
© Sachiko Ouchi 2019
SIMON FRASER UNIVERSITY
Summer 2019
Copyright in this work rests with the author. Please ensure that any reproduction or re-use is done in accordance with the relevant national copyright legislation.
ii
Approval
Name: Sachiko Ouchi
Degree: Master of Resource Management
Report No: 734
Title: Diversification within reduced fisheries portfolios signals opportunities for adaptation among a coastal Indigenous community
Examining Committee: Chair: Heather Earle Master of Resource Management Candidate
Anne Salomon Senior Supervisor Associate Professor
Colette Wabnitz Supervisor Research Associate Institute for the Oceans and Fisheries University of British Columbia
Christopher Golden Supervisor Assistant Professor Harvard TH Chan School of Public Health
Date Defended/Approved: August 19, 2019
iii
Ethics Statement
iv
Abstract
Understanding social-ecological mechanisms that promote or erode resilience to
potential disturbances can inform future adaptation strategies. Such mechanisms can be
illuminated among seafood dependent communities by documenting change in fisheries
portfolios, the assemblage of seafoods caught and/or consumed by a population of
fishers. Here, we collected expert knowledge to assess changes in an Indigenous
community’s fisheries portfolios and key drivers of change using semi-directed
interviews, a quantitative survey, and network analysis. We focused on fisheries caught
and consumed for food, social and ceremonial purposes. We found that while fisheries
portfolios decreased in their diversity of seafood types, they also became increasingly
connected, revealing that harvesters are diversifying their catch and the community is
eating a greater number of seafood types within increasingly depauperate portfolios.
These changes were driven by four key social-ecological mechanisms; 1) industrial
commercial activities under a centralized governance regime, 2) intergenerational
knowledge loss, 3) adaptive learning to new ecological and economic opportunities, and
4) trade in seafood with other Indigenous communities. Our results reveal that resilience
principles of diversity and connectivity can operate simultaneously in opposing
directions. Documenting changes in fisheries portfolios and local perceptions of key
social-ecological drivers can inform locally relevant adaptation strategies to bolster future
resilience.
Keywords: resilience; social-ecological systems; diversification; connectivity;
Indigenous food fisheries; expert knowledge
v
Acknowledgements
I would like to express gratitude for living, learning, and playing on the unceded
traditional territories of the sḵwx̱wú7mesh (Squamish), sel̓íl̓witulh (Tsleil Waututh), Stó:lō
(Sto:lo), and xʷməθkʷəy̓əm (Musqueam) Nations as an uninvited guest during my
graduate studies at Simon Fraser University. I would also like to acknowledge that I grew
up on the unceded territory of the Syilx (Okanagan) Peoples, to which I still call home.
My work is in collaboration with the ɬaʔəmɛn (Tla’amin) Nation and based within ɬaʔəmɛn
knowledge, to whom I would like to express my deepest gratitude for generously
teaching and sharing with me. As a settler I am privileged to access these bodies of
knowledge and I am humbled to work in these landscapes and seascapes.
Like a 1000-piece puzzle, this project was a labor of love. It would not have been
possible without the creative ideas, persistent hard work, and unwavering support of
many people fitting their piece into the larger picture.
First, I would like to acknowledge the contributions of my ɬaʔəmɛn collaborators
and co-creators of this project, Lori Wilson and Roy Francis. Your time, guidance and
ideas were integral components to our team that ultimately allowed us to produce this
project together. Thank you to all ɬaʔəmɛn knowledge holders who sat down to share
your stories with me and for trusting me with your knowledge. No amount of thank-you’s
could express the deep gratitude I have towards the broader ɬaʔəmɛn community,
especially Lee, Leonard, Scott, Alex and Jolene, Gerry, Drew, Luaifoas and the Howies.
Feeling welcomed, curious, and inspired are some of the many gifts you have given me
during my time spent in your home. Emote!
I would like to thank my supervisors and collaborators for guiding and supporting
me through thick and thin. Anne, your honest and insightful feedback, coupled with your
contagious warmth, encouraged and challenged me to think in a transformative manner.
I am deeply thankful for your mentorship and for the privileged learning experience.
Colette, your guidance, support, and wisdom gave me the motivation to step outside my
comfort zone for which I am forever grateful. Chris, thank you for sharing your “brain
child” and pushing me to think about links between the ocean and health. Anne
Beaudreau, I am grateful for the conversation that spurred a new avenue of methods
design and for your continued support.
vi
The project’s design and methods benefitted from the insights of so many:
Patricia Angkiriwang, Tiff-Annie Kenny, William Cheung, Laurie Chan, Evelyn Pinkerton,
Luke Rogers, Jenn Burt, Hannah Kobluk, Erin Slade, Skye Augustine, and all current,
incoming and outgoing members in the CMEC lab. I am also indebted to the REM staff
who have facilitated the behind-the-scenes workings to help us succeed in our
endeavours.
I am grateful for financial support from the School of Resource and
Environmental Management, Pacific Institute for Climate Solutions, SFU Community
Engagement, Canadian Institutes of Health Research and Natural Sciences and
Engineering Research Council.
Finally, I would like to send a thousand thank you’s to the amazing network of
family and friends that shaped and provided joy in my life. The love and support I feel to
chase down my passions are true blessings.
vii
Table of Contents
Approval ............................................................................................................................... ii Ethics Statement ................................................................................................................. iii Abstract ............................................................................................................................... iv Acknowledgements ..............................................................................................................v Table of Contents ............................................................................................................... vii List of Figures.................................................................................................................... viii List of Tables ..................................................................................................................... viii
Introduction ....................................................................................................................... 1
Methods ............................................................................................................................. 5 Study Area .......................................................................................................................... 5 Semi-Directed Interviews .................................................................................................... 5 Statistical Analyses ............................................................................................................. 7 Methodological advances, limitations and assumptions .................................................... 9
Results ............................................................................................................................. 11 Portfolios ........................................................................................................................... 11 Drivers of change .............................................................................................................. 12 Sensitivity analysis ............................................................................................................ 13
Discussion ....................................................................................................................... 14 Portfolio shifts.................................................................................................................... 14 Recommendations for adaptation opportunities in a Tla’amin Nation context ................ 21 Advancing Resilience Theory ........................................................................................... 22
Figures ............................................................................................................................. 23
Tables ............................................................................................................................... 30
References ....................................................................................................................... 32
Appendix........................................................................................................................... 42
viii
List of Figures
Figure 1. ɬaʔəmɛn harvest portfolios for pre and post 1980. Entire harvest portfolios (A,B) and core harvest portfolios (C,D) are shown. Cores were determined by being nodes with greater than or equal to the mean number of links in the network. Pre 1980 is comprised of 31 seafood types and represents 14 harvesters, whereas post 1980 is comprised of 28 seafood types and represents 17 harvesters. Node size represents the mean relative abundance, links between nodes represent at least one respondent reported harvesting both seafood types, and the layout of the network is represented with the Fruchterman-Reingold Algorithm* ........ 25
Figure 2. ɬaʔəmɛn consumption portfolios for pre and post 1980. Entire consumption portfolios (A,B) and core consumption portfolios (C,D) are shown. Cores were determined by being nodes with greater than or equal to the mean number of links in the network. Pre 1980 is comprised of 35 seafood types and represents 14 respondents, whereas post 1980 is comprised of 32 seafood types and represents 21 respondents. Node size represents the mean relative abundance, links between nodes represent at least one respondent reported consuming both seafood types, and the layout of the network is represented with the Fruchterman-Reingold Algorithm* .................................................................................. 27
Figure 3. Changes in portfolio composition (i.e. standardized degree centrality) and diversity (i.e. species richness) of harvest and consumption portfolios over time. Degree standardized degree centrality has significantly increased over time (A) while species richness decreases although the results are not significant (B). ****p<0.0001, *p<0.05 .............................. 28
Figure 4. Mean ranked perceived importance of each pre-identified factor for driving changes in food fish harvest and consumption over the last several decades. There is no significant difference in perceived importance of factors driving changes between harvest and consumption.................................................................................................................... 29
List of Tables
Table 1. Respondents' qualitative reasons for changes in the harvest and consumption of traditional seafoods, derived from an inductive analysis of themes. ..................................................................................................... 30
1
Introduction
Fisheries are quintessential social-ecological systems (SES) providing food and
nutritional security, livelihoods and cultural well-being for 3 billion people globally (FAO,
2016). However, projections of climate-induced fisheries declines (Barange et al., 2014;
Cheung, Watson, & Pauly, 2013; Lotze et al., 2019) suggest that eleven percent of the
earth’s population will become vulnerable to poor nutrition due to their reduced ability to
access marine foods (Golden et al., 2016). Repercussions of these declines are
predicted to intensify in coastal areas, where fish compose upwards of 70% of protein
consumed (FAO, 2016). Furthermore, multiple drivers of change, acting across a
diversity of spatial and temporal scales, are contributing to declining seafood catches to
which communities and ecosystems must adapt. These include, but are not limited to,
overexploitation (Costello et al., 2016), pollution (Fleming, Maycock, White, & Depledge,
2019), governance barriers (Plagányi et al., 2013), intergenerational knowledge loss
(Turner, Gregory, Brooks, Failing, & Satterfield, 2008), and cultural shifts (Tam, Chan,
Satter, Singh, & Gelcich, 2018). Adaptation in the face of multiple disturbances is a key
mechanism driving social-ecological resilience (Folke, Carpenter, Walker, Scheffer, &
Chapin, 2010), an emergent system property supported by attributes such as diversity,
knowledge integration, understanding of long-term change and polycentric governance
(Biggs et al., 2012). Here, by weaving traditional and western knowledge, we
investigated changes in the diversity and composition of a coastal Indigenous
community’s food fisheries over time and factors driving changes to inform future
adaptations that support SES resilience in light of current challenges and future
opportunities.
Emerging theoretical and empirical evidence suggests that ecological and/or
social diversity is a key property that confers system resilience by providing options by
which a system can respond to disturbances (Biggs et al., 2012). In aquatic systems,
diverse portfolios of populations (Schindler et al., 2010), species (Cline, Schindler, &
Hilborn, 2017), fisheries (Fuller, Samhouri, Stoll, Levin, & Watson, 2017) or livelihoods
(Cinner & Bodin, 2010) have been shown to be more resilient to multiple disturbances,
such as environmental, regulatory and economic pressures (Beaudreau et al., 2019),
than less diverse systems. Specifically, fisheries portfolios, are compositions of unique
2
species that are harvested by an individual or group using various fishing gears
(Beaudreau, Chan, & Loring, 2018). Adaptive responses can vary for different drivers of
change thus causing a disconnect between harvest portfolios and what is eaten by an
individual or group, or consumption portfolios. For example, increased market demand
for Pacific halibut might motivate fishers to sell their harvest and use that profit to buy
groceries from a store, which omits halibut from consumption.
Resilience can also be enhanced through the integration of knowledge systems
and learning (Biggs et al., 2012; Tengö, Brondizio, Elmqvist, Malmer, & Spierenburg,
2014). Weaving multiple knowledge sources can contribute new evidence, provide
opportunities to learn from one another, and improve the capacity to interpret the
dynamics of SES (Tengö et al., 2014) and inform how communities might adapt. For
example, perspectives from multiple regions and sectors (Chan, Beaudreau, & Loring,
2018), and from local communities (Bennett, 2016) can provide a more complete picture
of environmental, social and cultural changes being experienced by people. Thus,
successful changes in conservation science rely on knowledge from impacted
communities (Bennett, 2016; Gelcich et al., 2014). Experimental, iterative, and reflective
learning are important for understanding uncertainties and complexities of SES, which is
essential for enabling an adaptation response of communities to changing conditions
(Biggs et al., 2012; Faulkner, Brown, & Quinn, 2018).
Understanding and managing long-term, slow-variables and feedbacks
underlying SES dynamics is a resilience principle linked closely to learning and
knowledge integration. Interpreting long-term drivers of change requires data or
knowledge sources that have an expansive time horizon. More often than not, western
science is limited in its temporal depth. However, knowledge from local people (e.g.
Traditional Ecological Knowledge or TEK) can enrich the picture by providing information
and knowledge passed down across generations (Huntington, 2000; Tengö et al., 2014).
These multiple sources of knowledge can be used to make sense of and respond to
feedbacks from the environment thus facilitating adaptive governance, which is rooted in
collaborative decision-making processes to adaptively negotiate and coordinate
management of SESs (Berkes, Colding, & Folke, 2000; Schultz, Folke, Österblom, &
Olsson, 2015).
3
On the Pacific coast of Canada, current fisheries governance regimes are limiting
Indigenous people’s access to fish (Harris, 2009; Jones, Rigg, & Pinkerton, 2017;
Pinkerton & Davis, 2015; von der Porten, Lepofsky, McGregor, & Silver, 2016), thereby
exacerbating predicted climate-induced shortages in traditional seafoods’ catch potential
(Cheung, Brodeur, Okey, & Pauly, 2015; Weatherdon, Ota, Jones, Close, & Cheung,
2016). Given these interlinked, cross-scale, social-ecological drivers of change, a perfect
storm is brewing where communities most dependent on the marine environment for
food are also the most vulnerable to climate change and inequitable governance
regimes (Allison & Bassett, 2017; Golden et al., 2016). Therefore, there is a pressing
need to understand current and future barriers and opportunities to improve access to
traditional marine foods and design management strategies that are socially-just,
ecologically-sustainable and reflect community priorities and local knowledge (Salomon
et al., 2018).
Coastal Indigenous people in British Columbia (BC), Canada, self-referred to as
First Nations (FN), depend on marine resources for food, social and ceremonial (FSC),
as well as economic purposes (Jones, Shpert, & Sterritt, 2004). However, FN peoples in
BC are facing high rates of food insecurity, where up to 41% of households on reserve
have limited access to food/or cannot meet their nutritional needs (Chan et al., 2011).
Moreover, potential catches of both commercial and FSC marine seafoods along the
coast are projected to decrease by 4.5 to 10.7% with increased magnitude of change
expected at lower latitudes (Weatherdon et al., 2016). Thus, future food insecurity is
predicted to be exacerbated. In addition, new generations of coastal FN are transitioning
away from traditional foods due to limited access of traditional marine resources (Chan
et al., 2011) and generational changes in food preference (Kuhnlein & Receveur, 1996).
Developing strategies to adapt to climate change and to contest inequitable governance
regimes is crucial for coastal FN to continue to have sustainable fisheries and healthy
human communities in the future.
Here, in collaboration with the ɬaʔəmɛn (Tla’amin) Nation, we collected
knowledge from traditional food fisheries knowledge experts to document change in the
composition, diversity and relative abundance of fisheries harvested and consumed over
the last eighty years, and identify key drivers of these changes. We hypothesized
multiple non mutually exclusive mechanisms may be contributing to two portfolio
outcomes over time. First, traditional food fisheries portfolios could diversify over time
4
and become more connected due to 1) serial depletion of culturally preferred species
(Salomon, Tanape, & Huntington, 2007) resulting in a shift to multiple new target species
(Roughgarden, 1972; Schoener, 1971), 2) a change in target species preferences
(Beaudreau, Chan, & Loring, 2018), and/or 3) advances in fishing technology increasing
access to new target species. Alternatively, portfolios could have become less diverse
due to 1) license restrictions (Ojea, Pearlman, Gaines, & Lester, 2017), 2) reduced
fisheries abundance due to environmental factors such as climate change (Weatherdon
et al., 2016), and/or 3) increasingly prohibitive economic costs of fishing (Pinkerton &
Edwards, 2009). Lastly, we hypothesized that these multiple mechanisms may be
operating concurrently influencing the diversity and connectivity of harvest and
consumption portfolios in opposing directions.
5
Methods
Study Area
We conducted this research in collaboration with the Tla’amin Nation (formerly
Sliammon First Nation) on the southwest coast of British Columbia (BC), Canada (Figure
A1). ɬaʔəmɛn (Tla’amin) people have occupied their traditional territory on the northern
Salish Sea for at least the last millennium (Lepofsky et al., 2015; Springer & Lepofsky,
2019). Archaeological evidence suggests ɬaʔəmɛn people relied on and actively
managed a diversity of marine resources throughout this time period (Caldwell et al.,
2012). Since colonization in the late 1700’s, profound socio-economic, ecological and
cultural drivers of change have transformed ɬaʔəmɛn way of life (Paul, Raibmon, &
Johnson, 2014). These include mandatory beach closures due to contamination (Fediuk
& Thom, 2003), marine resource shifts in the Salish Sea due to industrialized fishing
(Pauly, Pitcher, & Preikshot, 1998), and the imposition of residential school (L. Barnes,
2008; Paul et al., 2014). In 2016, the Tla’amin Nation ratified a treaty with the
Government of Canada and BC specifying Tla’amin Nation’s rights and benefits
respecting land, marine and terrestrial resources, and self government (Tla’amin Final
Agreement, 2016). This is a unique governance context among FNs in BC in that most
of BC crown land is unceded, meaning that Aboriginal Title has neither been
surrendered nor acquired by the Government of Canada. Although ɬaʔəmɛn people have
experienced centuries of rapid changes, harvesting and eating marine foods continues
to be a central component of cultural and day-to-day practices for most members of the
community (Chan et al., 2011; Paul et al., 2014).
Semi-Directed Interviews
Respondent Selection. To assess changes in ɬaʔəmɛn food fisheries portfolios
through time, we conducted semi-directed interviews (Huntington, 1998) with ɬaʔəmɛn
traditional food fisheries knowledge experts (n=24) during June to August of 2018. Our
objective was to target expert knowledge holders rather than taking a representative
sample of community members. Consequently, community experts were identified and
selected based on their expertise of traditional food fisheries (Davis & Wagner, 2003;
Fazey, Fazey, Salisbury, Lindenmayer, & Dovers, 2006; Salomon et al., 2007) and deep
6
knowledge of the system, making them highly suited to detect changes in harvesting and
consuming traditional seafoods (Ban et al., 2017), and the factors driving this change
(Andrachuk & Armitage, 2015). Initial ɬaʔəmɛn traditional food fisheries experts were
identified by our Tla’amin Nation research partners with additional experts identified from
conversations with initially interviewed experts (Beaudreau et al., 2018; Olsson, Folke, &
Hughes, 2008). Depending on factors, such as ‘age’, ‘occupation’ and ‘preference not to
answer’, not all respondents were represented in each portfolio (Table A1). We
interviewed five female experts and 19 male experts. The age range of experts spanned
28-87 years old. In addition to variation in sample size of respondents, there is variation
in the number of seafood types reported in each portfolio (Table A1).
Traditional Food Fisheries Portfolio Survey Design. Portfolios are
composition of harvested (or consumed) seafoods by groups or species. Traditional food
fisheries were defined by the community, through Traditional Use Study documents
and/or our interviews, which included finfish and shellfish used for food, social and
ceremonial (FSC) purposes. We asked experts to rank the relative abundance of
traditional food fisheries, harvested and consumed, on an ordinal scale from 1 (low) to 7
(high), for the current decade (“current”, 2010-2018) and the earliest decade for which
the expert had memories of harvesting or consuming (“past”). Relative abundances were
ranked for different food fisheries groups (n=35), hereafter termed seafood types (Table
A2). Not all seafood types were ranked by all experts.
Drivers of Change Survey Design. We also asked experts to identify and rank
factors according to the perceived importance of driving change, from their “past” to
“current” decade, in traditional food fisheries harvest and consumption, separately. First,
qualitative responses were documented, as to minimize bias and elicit personal,
unfiltered responses (Gelcich et al., 2014). Second, experts ranked ten pre-identified
factors, on an ordinal scale from 1 (low) to 7 (high), that were identified by our Tla’amin
Nation partners and included factors driving changes in other areas of coastal BC
according to the literature (Table A3). During the interviews, we took detailed notes of
stories, anecdotes, observations and knowledge to triangulate and inform our inference
of the quantitative data generated by the survey and to provide a more complete
understanding of potential changes in traditional food fisheries (Jick, 1979). Prior to
these interviews, three pilot interviews with our Tla’amin Nation partners were conducted
7
to test and refine our questions to improve interpretation and consistency among
respondents.
Statistical Analyses
Portfolio Analysis
To assess how the composition, diversity and relative abundance of ɬaʔəmɛn
traditional food fisheries have changed through time we conducted a network analysis of
ɬaʔəmɛn food fisheries portfolio. First, respondents’ harvest and consumption portfolios
were aggregated into responses pre and post 1980 due to two punctuated events that
drove profound changes in regional fisheries: the North Pacific oceanic regime shift in
1977 (Anderson & Piatt, 1999; Hare & Mantua, 2000), and the collapse of Pacific herring
from t̓išosəm (Sliammon Village) in the early 1980’s (pers. comm. of many ɬaʔəmɛn
harvesters; Paul et al., 2014). Harvest and consumption portfolios were aggregated and
analyzed separately.
Second, we used network analysis, specifically the igraph package in R (Csárdi
& Nepusz, 2019) to calculate and depict how the composition of harvest and
consumption portfolios changed between pre and post 1980. Specifically, we calculated
degree centrality (see below for definition) as a metric of composition, species richness
as a metric of diversity, and ranked relative abundance of all seafood types (Beaudreau
et al., 2018). Portfolio nodes (spheres) in the network represent traditional seafood types
(e.g. clams, herring, sockeye, etc.). The next steps are outlined for harvest, but the same
procedures were followed to represent consumption portfolios. We relativized the ordinal
score for each seafood type provided by each respondent, by dividing this score by the
total relative abundance score for all seafood types by the respondent. Here, the size of
each portfolio node is proportional to the mean relativized score across all respondents.
Portfolio links (lines) connecting spheres represent at least one respondent having
reported harvesting both of the seafood types for a given time period. The thickness of
the lines represents the proportion of respondents that reported harvesting both seafood
types in the associated time period. Position of the nodes in space represents how
commonly a seafood type is reported among respondents. Seafood types aggregated in
the center of the portfolio are more commonly reported, whereas seafood types located
at the edges are less commonly reported. Finally, portfolios were visualized in two ways.
8
First, as the entire network including all seafood types reported by experts and second,
focusing on seafood types with greater than the mean number of links.
To quantify degree centrality we used standardized degree centrality, which is
the relativized number of links associated with one seafood type (Freeman, 1979).
Seafood types with higher standardized degree centrality are of more importance in the
portfolio because of their high connectivity to other seafood groups; thus they are more
commonly harvested or consumed. To test for an effect of time period on standardized
degree centrality of the entire portfolio (i.e. an aggregate number for each seafood type
among respondents) we applied a beta linear regression model, namely the betareg
(Cribari-Neto & Zeileis, 2010; Zeileis et al., 2019) package in R, which allowed us to use
proportions. Specifically, we used a beta distribution with a Maximum Likelihood
estimation and logit link. To accommodate the upper bounds of the beta distribution, we
transformed the standardized degree: y’ = [y (N – 1) + 0.5]/N, where N is the sample size
(Smithson & Verkuilen, 2006).
To test for an effect of time period on seafood type diversity between pre and
post 1980, we ran a linear mixed effects model with respondent as a random effect given
that each diversity value was associated with individual respondents. We used a
Poisson likelihood, log link function and the lme4 package in R (Bates et al., 2019).
Given this model fit, we used a Wald Chi2 test statistic with the car package in R (Fox et
al., 2019) to test for the effect of time period on diversity.
Finally, to test for an effect of time period on the mean relative abundance for each
seafood type we used a beta linear regression model (as described above) to account
for the fact that the relativized relative abundance scores are proportions of each
respondents’ total relative abundance score.
Drivers of Change Analysis
To test for a difference in the perceived relative importance of drivers of change
(i.e. different factors driving change) for traditional seafood harvest and consumption, we
constructed an ordinal logistic mixed-effects model with a cumulative link function that
accounted for the ranked nature of our data (Hedeker, 2008). Rankings between distinct
numbers on the ordinal scale were rounded up to the nearest distinct level (e.g. 5.5 to 6)
to minimize the number of distinct groups in our model. We treated respondent as a
9
random effect and used the ordinal package in R (Christensen, 2019). We identified the
minimum adequate model based on Akaike’s Information Criterion (AIC) using the
AICcmodavg package in R (Mazerolle, 2019). We used a likelihood ratio test to test for
significant differences in ranked importance of drivers of change using the car package
(Fox et al., 2019).
Second, to test for differences in the importance among drivers of change
between harvest and consumption, we constructed a second ordinal logistic mixed-
effects model in the same format as above. We used likelihood ratio tests for main
effects and interactions to evaluate the effect of harvesting versus consumption on
perceived importance of factors driving change using the car package (Fox et al., 2019).
A spider diagram was used to visualize these results. Finally, we analyzed experts'
qualitative reasons for shifts in harvest and consumption portfolios, previous to pre-
identified factors above, using inductive coding of themes (Creswell & Poth, 2017).
Sensitivity Analyses. To test the adequacy of the sample size of experts, we
calculated a species accumulation curve (Gotelli & Colwell, 2001) for harvest and
consumption portfolios. Since network analysis is sensitive to missing data (Smith,
Moody, & Morgan, 2017), sensitivity analyses were also conducted on the harvest and
consumption portfolio’s links (lines connecting nodes) and nodes (seafood types)
themselves. Nodes were bootstrapped in increased proportion (0.5, 0.6, 0.7, 0.8, 0.9,
1.0) of total number of seafood types for 100 iterations without replacement. Links were
bootstrapped with 80% of the total for 100 iterations without replacement.
Methodological advances, limitations and assumptions
Our methodology advances a mixed-methods approach spanning disciplinary
boundaries. First, the contribution of Indigenous Knowledge to the analyses, lends
legitimacy to this research within the Nation (Pinkerton & John, 2008) and bridges
anthropological and ecological disciplines (Tengö et al., 2014). Second, by comparing
past and present decades, it allowed us to increase the time horizon of interest since
experts are of different ages. Thus, we are able to explore long term trends and drivers
of change to capture the socio-economic, ecological and cultural changes that the
community has undergone in the time frame of the study and differentiate how much that
is reflected in both harvesting and consumption patterns. Although this doesn’t reduce
10
variation around respondents, it accurately portrays the human experience and life lived
as a ɬaʔəmɛn person (Paul et al., 2014). Furthermore, as respondents shared
information on different time periods there is uncertainty in the resulting variability of the
data. For example, younger respondents might not be able to identify slower, long-term
drivers of change (e.g. intergenerational knowledge loss) compared to that of an older
individual (Tam et al., 2018). However, we found that respondents were better able to
recall distinct differences over coarse grain time periods compared to finer grain, decade
by decade differences.
Given the nature and design of our study, our methodology is not without
limitations and assumptions that accompany human sources of information. We report
expert observations and knowledge which, like all forms of data, are subject to variation,
uncertainty, and bias (Hilborn & Mangel, 1997). Experts were asked to recall information
from a time in their childhood that is vulnerable to shifting baseline syndrome (Papworth,
Rist, Coad, & Milner-Gulland, 2009; Pauly, 1995) and recall bias (Golden, Wrangham, &
Brashares, 2013; O’Donnell, Pajaro, & Vincent, 2010). Furthermore, humans are
influenced by their cultural context and observations will reflect these experiences
(Berkes et al., 2000). Nonetheless, if temporal references are established, recalled
observations after 50 years can be relatively accurate (Berney & Blane, 1997). Here, we
used early childhood memories and spent time at the beginning of the interview
establishing reference points by recalling stories and life events that coincide with that
time period. In addition, other socio-economic factors, such as switch behavior of
fisheries due to economic incentives or availability of other species (Daw, 2010), can
influence our inferences. However, we accounted for these differences by asking experts
about what factors are driving changes. Finally, our objective was to elicit knowledge
from experts of traditional seafood harvest and consumption, thus our sample size is
limited due to the limited number of experts in the resource system.
11
Results
Portfolios
Composition. We detected a significant difference in traditional fisheries harvest
and consumption portfolios composition pre and post 1980 (Figure 1, 2). Specifically,
standardized degree centrality was significantly higher post versus pre 1980 for both
harvest (Z = 2.21, p = 0.03) and consumption (Z = 4.51, p = 6.43e-6) portfolios (Figure
3A).
Diversity. We found no significant effect of time period on the diversity of
seafood types within harvest (2 = 0.82, df = 1, P = 0.37) or consumption (2 = 0.57, df =
1, P = 0.45) portfolios (Figure 3B), although the number of seafood types caught and
consumed tended to be lower post 1980. We found differences in the types of seafoods
caught versus consumed. Specifically, northern abalone (Haliotis kamtschatkana),
Eulachon (Thaleichthys pacificus), Pacific Sardine (Sardinops sagax) and Longnose
Skate (Raja rhina) were consumed, but not harvested by ɬaʔəmɛn community members.
Relative Abundance
I. Harvest Portfolios
We found a significant effect of time period on the relative abundance of some,
but not all, seafood types harvested pre and post 1980 (Table A4). Significant decreases
(p < 0.05) include Pacific Herring (Clupea pallasii pallasii, -37.6%) and Pacific Herring
roe (-31.1%), Lingcod (Ophiodon elongatus) eggs (-14.4%), red sea urchin
(Mesocentrotus franciscanus, -11.1%), green sea urchin (Strongylocentrotus
droebachiensis, -8.9%), Perch (Embiotocidae, -7.9%), Flounder (Paralichthyidae,
Pleuronectidae, -7.9%), harbour seal (Phoca vitulina, -7.9%), Black Cod (Anoplopoma
fimbria, -7.4%), red sea cucumber (Parastichopus californicus, -7.4%), pacific geoduck
(Panopea abrupta, -7.1%), Spiny Dogfish (Squalus suckleyi, -6.2%), scallops (Chlamys
hastata, Crassadoma gigantean, -6.2%), and northern giant pacific octopus
(Enteroctopus dofleini, -5.9%). We detected no significant change in the relative
abundance of the remaining species, including but not limited to any salmon species
(Oncorhynchus spp.), clams (Saxidomus giganteus, Protothaca staminea, Venerupis
12
philippinarum, Clinocardium nuttallii), Pacific Halibut (Hippoglossus stenolepis) and spot
prawns (Pandalus platyceros) between pre and post 1980 in harvest portfolios.
Furthermore, although some seafood types were reportedly higher post 1980, we
detected no significant increases in harvested seafood types pre versus post 1980.
II. Consumption Portfolios
Similar to harvest portfolios, we found a significant effect of time period on the
relative abundance of some, but not all, seafood types consumed pre and post 1980
(Table A5). However, unlike ɬaʔəmɛn harvest portfolios, we detected significant
increases (p < 0.05) within ɬaʔəmɛn consumption portfolios post 1980 for Pacific Halibut
and spot prawns - 16.3% and 21.8%, respectively. Time period had a significant
negative effect (p < 0.05) on the relative abundance of other seafood types, including:
Pacific Herring (-35.3%) and Pacific Herring roe (-18.6%), Lingcod eggs (-25.0%), red
sea urchin (-16.1%), Pink Salmon (Oncorhynchus gorbuscha, -16.0%), green sea urchin
(-15.7%), harbour seal (-15.4%), Pacific Tomcod (Microgadus Proximus, -14.6%), Coho
Salmon (Oncorhynchus kisutch, -14.5%), Perch (-14.4%), Black Cod (-14.2%),
Longnose Skate (-14.1%), Spiny Dogfish (-13.6%), clams (-13.2%), red sea cucumber (-
13.1%), Flounder (-13.0%), pacific geoduck (-12.8%), purple sea urchin
(Strongylocentrotus purpuratus, -12.0%), Eulachon (-11.4%), Kelp Greenling
(Hexagrammos decagrammus, -10.6%), northern abalone (-10.1%), and northern giant
pacific octopus (-10.1%). We detected no significant difference between pre and post
1980 for the remaining seafood types. Overall changes in relative abundance of seafood
types can be visualized in both harvest and consumption portfolios (Figure 1, 2).
Drivers of change
Quantitative Responses. We found a significant difference in the perceived
relative importance of factors driving changes in harvest (Likelihood Ratio Chi2 = 75.33,
df = 9, p = 1.34e-12) and consumption (Likelihood Ratio Chi2 = 76.86, df = 9, p = 6.77e-13)
portfolios. Permit Barrier had the lowest mean ranked importance, while Ocean Pollution
and Commercial Overharvesting had the highest for factors driving changes in both
harvest and consumption portfolios. We found no evidence to support the addition of
respondent co-variates (e.g. age or gender) to explain the variation in the ranked
importance of divers of change (Table A6). Furthermore, we found no significant
13
difference in the interaction between drivers of change and portfolio type (Likelihood
Ratio Chi2 = 1.86, df = 9, p = 0.99; Figure 4).
Qualitative Responses. Respondents identified drivers of change for shifts in
harvest and consumption portfolios previous to ranking the above mentioned pre-
identified factors. These factors fell into 12 themes (Table 1), with Modernization,
Environmental change, and Change in diet among the most frequently reported - 50%,
42% and 38%, respectively. Although most factors aligned with our pre-identified factors,
such as Environmental change, Overharvesting, Access, Governance barriers, Change
in diet, Pollution, and Knowledge loss, there were factors identified by our experts that
we had not considered. These included Self-government, Modernization, Employment,
Change in traditional values, Predation, Technology, and Community dependence.
Sensitivity analysis
Our species accumulation curves showed saturation for post 1980 but did not
saturate for pre 1980 (Figure A2). Therefore, we obtained complete portfolios post 1980
whereas we may not have for pre 1980 due to limited experts (n = 14; Table A1) with
knowledge from earlier time periods (i.e. knowledge holders who have passed on).
However, results from our sensitivity analysis (see below) increases confidence in our
inferences. We found that node sensitivity analysis (i.e. changing proportions of seafood
types considered) and link sensitivity analysis (i.e. a subset of relational links between
seafood types) showed no difference in results for an effect of time on standardized
degree centrality for both harvest (Node: all proportions p < 0.05, Link: Z = 19.89, p < 2e-
16; Figure A3, A4) and consumption portfolios (Node: all proportions p < 0.05, Link: Z =
40.76, p < 2e-16; Figure A3, A4).
14
Discussion
A growing body of evidence suggests that enhanced connectivity and diversity
within social-ecological systems (SES) confers resilience to a broad array of
disturbances (Biggs et al., 2012; Cinner & Bodin, 2010; Folke, Biggs, Norström, Reyers,
& Rockström, 2016; Janssen et al., 2006), which is also found to be true among fishing-
based communities worldwide (Beaudreau et al., 2019; Cinner & Bodin, 2010; Fuller et
al., 2017; Stoll, Fuller, & Crona, 2017). Paradoxically, we found that while ɬaʔəmɛn
fisheries portfolios decreased in the diversity of different seafoods harvested and
consumed after 1980, they became significantly more connected (Figure 3). Although a
fewer number of total seafood types are being harvested and consumed nowadays,
more harvesters are diversifying their catch and consuming a greater number of seafood
types within these depauperate portfolios. Social-ecological mechanisms reported by
experts as responsible for driving these trends include industrial commercial resource
use, centralized governance, intergenerational knowledge loss, adaptation to new
markets and ecological opportunities, as well as increased connectivity among
communities via the trade in seafood. In addition to these mechanisms, experts
perceived commercial overharvesting and pollution as the most important disturbances
driving shifts in fisheries portfolios, while issues surrounding access rights, now granted
by Tla’amin Nation government, was perceived as less important. Our results advance
resilience theory and practice by illuminating novel mechanisms driving this emergent
system property and informing locally relevant adaptation strategies to bolster future
resilience in this system.
Portfolio shifts
More connected and less diverse portfolios
We found that ɬaʔəmɛn harvest and consumption portfolios are more connected,
yet less diverse now compared to past decades. Specifically, we found that mean
centrality scores of both harvest and consumption portfolios were higher post 1980 while
the number of different seafoods was smaller. Decreases in portfolio diversity among
respondents were driven, in large part, due to the declines in traditional seafoods such
as Pacific Herring, sea urchin, sea cucumber, Lingcod eggs and seal harvested and
15
consumed by community members on average (Figure 3B). This is also evident in
shifting portfolio configurations. Specifically, these seafood types shift from the core of
portfolios to the periphery (Figure 1, 2). Concurrently, popular seafoods, such as salmon,
rockfish, and crab, are being caught and consumed by more people leading to increases
in portfolio centrality scores, reflecting enhanced connectivity among seafood types. The
emergence of new fisheries for deep water benthic species, such as spot prawns and
Pacific Halibut, are becoming increasingly accessible by more harvesters also resulting
in increased connectivity in portfolios. These seafood types are now central, core
species in ɬaʔəmɛn portfolios whereas they previously were located on the periphery
(Figure 1, 2). Furthermore, less common seafood types such as seal, Perch, and
Longnose skate have been lost entirely from portfolios leading to a decrease in diversity
and an overall more connected core over time.
We also detected differences in the relative abundance of various seafood types
among ɬaʔəmɛn harvest and consumption portfolios. For example, spot prawns and
Pacific Halibut consumption has increased by 16.3% and 21.8% post 1980 while harvest
of key traditional seafood, such as Pacific herring, Lingcod eggs, and sea urchins, have
significantly decreased by 37.6%, 14.4% and 8.9 – 11.1 % respectively (Figure 1, 2;
Table A4, A5). While there were dramatic changes in the amount of some seafood types
harvested or consumed, others remained relatively constant and core species in
portfolios (e.g. salmon, crab, and rockfish). These patterns in connectivity, diversity and
relative abundance are driven by several key social-ecological mechanisms illuminated
by experts in the community.
Social-ecological mechanisms driving shifts in portfolios
Our quantitative and qualitative analyses revealed four key social and ecological
mechanisms responsible for the changes detected among harvest and consumption
portfolios. Specifically, industrial commercial activities under the authority of a
centralized governance regime, intergenerational knowledge loss, learning and adapting
to new ecological and economic opportunities, and the trade in seafood among coastal
FN communities were all attributed to the major changes we documented, revealing both
the erosion and rebuilding of resilience attributes among the ɬaʔəmɛn community over
the past eight decades.
16
I. Industrial commercial activities under centralized governance
Access to traditionally important seafoods have been significantly reduced by
industrial commercial activities, such as fishing and logging, currently under the authority
of a centralized governance regime. In ɬaʔəmɛn territory, this is exemplified by Pacific
Herring where the harvest and consumption of this forage fish and its eggs has
significantly decreased in relative abundance (Table A4, A5). While herring remain
relatively central seafood types in portfolios (Figure 1, 2) revealing their cultural
importance, this food fishery is no longer as available. Experts reported that herring were
“fished out” of ɬaʔəmɛn waters in 1983 and that commercial fisheries targeting adult
females for their roe was the main driver of this change (pers. comm. of many ɬaʔəmɛn
harvesters; Paul, Raibmon, & Johnson, 2014). Such reports are consistent with other
academic literature addressing Pacific Herring collapse (Cleary, Cox, & Schweigert,
2010; Essington et al., 2015).
“The herring spawn. And this whole area would be just white. It’s t̓išosəm – the water is “milky.” That’s why people started calling this place “t̓išosəm.” Because of that… Now we don’t get herring anymore. It is all cleaned out. Several years ago, they opened seine fishing in this area. This whole area was lit up front of the village from Sliammon to Scuttle Bay towards Powell River, over to Harwood. There were all kinds of seine boats out there. And they scooped up all the herring. We never did get herring after that” Paul et al., 2014, pp. 115–116.
This has large economic and cultural consequences for Tla’amin Nation and ɬaʔəmɛn
people. For this reason, commercial overharvesting was perceived by experts as one of
the most important drivers of change in harvest and consumption portfolios (Figure 4).
Past decisions to open herring fisheries were solely in the hands of Canada's federal
fisheries agency, Department of Fisheries and Oceans (DFO). Ultimately, the fisheries
Minister still retains the discretion to open the fishery regardless of the science and other
knowledge sources provided (Klain, Beveridge, & Bennett, 2014). Moreover, Indigenous
livelihood and lifestyle objectives have not yet been incorporated in herring management
(von der Porten et al., 2016). For example, even though Strait of Georgia herring stocks
are reported as “spawning biomass is at a historic high” (DFO, 2019), ɬaʔəmɛn people
have knowledge of how their waters were white with herring spawn in the past, thus wish
to conserve stocks such that they might return to tʼɩšosəm (pers. comm. Hegus Clint
Williams). As of 2016, Tla’amin Nation is party to a joint fisheries committee with
neighbouring FNs and DFO to facilitate learning and shared decision making (Tla’amin
17
Final Agreement, 2016). As a treaty Nation with rights recognized by the Government of
Canada and BC, it explains why access granted by the Nation was not perceived as an
important barrier by experts in the community (Figure 4).
Additionally, logging related activities, such as the local pulp mill and associated
contamination levels, under the authority of a centralized governance regime have
decreased harvest and consumption of clams (pers. comm. Eugene Louie). Although
clams are still centrally important traditional seafoods for ɬaʔəmɛn harvest and
consumption portfolios (Figure 1,2), their relative abundance have decreased due to
beach closures associated with pulp mill contamination and high fecal coliform levels.
“We don’t get clams in front of our community anymore because it is all contaminated”
(Paul et al., 2014, p. 117). Pollution was also perceived as the most important driver of
change amongst experts. Furthermore, although some beaches might be safe to
harvest, ultimately the decision to continue beach closures resides with federal
governing authorities that often operate with limited resources and available data.
Finally, predation by marine mammals, such as seals and sea lions, and a lack of
participation in the decisions surrounding these predator populations was identified
qualitatively as an important driver of change among portfolios (Table 1). Traditionally,
seals were hunted and managed by ɬaʔəmɛn people (Paul et al., 2014) but are no longer
represented in harvest or consumption portfolios post 1980 (Figure 1, 2). As predators of
a diversity of benthic and pelagic fish, such as salmon and Pacific Herring, seals and
sea lions compete with humans and other culturally important species (e.g. killer whales
- Chasco et al., 2017) for food. Currently, Canada’s federal fisheries agency, DFO, has
the authority to manage these marine mammals, which further centralizes governance
and limits opportunities for the revitalization of traditional management systems.
Current centralization of decision-making power can reduce resilience by limiting
learning across multiple scales and eroding trust in management (Biggs et al., 2012).
However, resurgence of Indigenous governance can confer resilience and promote
transformation by elevating rights of local communities, enabling knowledge co-creation
and knowledge sharing (Abson et al., 2017; Faulkner et al., 2018; Folke, Hahn, Olsson,
& Norberg, 2005; Galafassi et al., 2018), and facilitating food sovereignty (Walsh-Dilley,
Wolford, & McCarthy, 2016). For truly transformational change, shared decision making
between governments can equalize power distribution (Salomon et al., 2018), integrate
18
diverse sources of knowledge (Tengö et al., 2014), cooperatively manage natural
resources (Jones et al., 2017), and lead to more resilient SESs (Biggs et al., 2012).
II. Intergenerational knowledge loss
Reduced diversity among ɬaʔəmɛn fisheries portfolios was also driven in part by
the loss of knowledge of specific harvesting practices among generations. For example,
the loss of seal from harvest and consumption portfolios and substantial decrease in
abundance of traditionally important seafoods, such as Chum salmon, Lingcod eggs,
and red and green sea urchins, were attributed to a lack of knowledge among younger
generations on how to collect and process these traditionally important seafoods (Figure
1, 2). Although there is still an abundance of these seafood types in the ocean, the
active practice of harvesting and consuming these traditional foods has decreased: there
are “still many sea urchins out there [in the marine environment], but no one wants them.
I will only go get them if an elder is wishing for them” (pers. comm. Lee George). As
intergenerational knowledge loss increases, participation declines, which can erode SES
resilience by hindering learning opportunities and impedes collective action required to
respond to disturbance and changes (Biggs et al., 2012). Fewer youth involved in
traditional practices perpetuates a reduction in knowledge transfer and reduces the
likelihood of cultural preservation with changing futures (Turner et al., 2008).
III. Adapting to new ecological and economic opportunities
Learning and adapting to new ecological and economic opportunities has been a
key mechanism driving changes in ɬaʔəmɛn harvest and consumption portfolios. For
instance, spot prawn has become a more central component of both harvest and
consumption portfolios over time, reportedly due to increased market demand for these
same species in regional commercial fisheries (British Columbia Seafood Industry: Year
in Review 2016, 2016) and modern fishing gear that facilitates access to deep water
fisheries. Spot prawns were not a traditionally important food fishery, however ɬaʔəmɛn
harvesters have learned to adapt to this new opportunity and harvest them for food in
association with the commercial fishery. In addition, Pacific Halibut have been “moving
into the area” (pers. comm. Lee George), which has increased their harvest and
consumption as people adapt to the increased availability and accessibility of this
species. Furthermore, halibut is now offered as a part of the Tla’amin Nation’s
19
community food fish program in place of previously abundant seafood types like Fraser
River Sockeye Salmon when Sockeye are unavailable. Both learning and adapting to
new opportunities are key characteristics of resilience (Biggs et al., 2012). However,
human health could be negatively impacted if these trends continue since salmon
species are nutritionally different from halibut, especially in terms of fatty acids, which is
a required nutrient that salmon provide 70% of in FN diets (Marushka et al., 2019).
Moreover, continuously shifting to new fishing opportunities could lead to the serial
depletion of species as previously abundant seafood types become less abundant
(Armstrong, Armstrong, & Hilborn, 1998; Karpov, Haaker, Taniguchi, & Rogers-Bennett,
2000; Salomon et al., 2007).
IV. Increased connectivity among communities via trade of seafood
While consumption and harvest portfolios both decreased in diversity, they also
had clear differences in their content, in part due to the trade of seafood among coastal
communities. For example, while Pacific Herring are no longer as abundant in ɬaʔəmɛn
waters now relative to the decades prior to 1980 (pers. comm. of many ɬaʔəmɛn
harvesters; Paul, Raibmon, & Johnson, 2014), many people obtain herring eggs to
consume from other Indigenous communities along the coast, primarily the Heiltsuk
Nation who have an active herring spawn-on-kelp food fishery (pers. comm. Paul
August). Eulachon is another seafood type that is traded for with other Nations since it is
consumed but not harvested by ɬaʔəmɛn people in their traditional territory. Here, trade
of seafoods with other Nations supports coast-wide connectivity which and facilitates
continued familial and economic relationships thereby enhancing resilience to local
disturbance (Biggs et al., 2012). However, the use of herring eggs and Eulachon has
decreased over time due to changes in traditional diet and in people’s taste, suggesting
that decreased participation in these fisheries could reduce SES resilience. This also
has implications for Indigenous health in that these forage fish provide essential
nutrients, such as vitamin A and fatty acids, in traditional diets (Marushka et al., 2019).
Implications for Resilience Theory
Diversification and connectivity within fisheries portfolios can play an essential
role in fishers’ adaptive capacity (Beaudreau et al., 2019; Cinner et al., 2015; Stoll et al.,
2017) and thus contribute to overall resilience of SESs (Biggs et al., 2012). For example,
20
increased connectivity (i.e. centrality) between different seafood types provides
communities with capacity to adapt to changes by decreasing vulnerability to
perturbations due to a reduced dependence on only a few seafood types. Therefore,
adaptive capacity and decreasing sensitivity to disturbances is conferred by shifting
among fisheries (Fuller et al., 2017). Moreover, decreased centralization of the entire
network (i.e. increased connectivity between seafood types) increases the robustness of
the removal of nodes in network analysis (Janssen et al., 2006) by facilitating the option
to fish other species when necessary. Increased portfolio connectivity also suggests
increased participation in harvesting (or consuming) more seafood types among more
people. This potentially indicates increased equity (Bodin, Crona, & Ernstson, 2006;
Janssen et al., 2006) in the system by increasing the ability of fishers to access different
seafood types previously inaccessible. Similarly, learning over time to harvest new
species that emerge in the SES can bolster resilience in SESs (Biggs et al., 2012).
Concurrently, increased diversity of seafood types provides increased harvest flexibility
to adapt to changing conditions (Beaudreau et al., 2018; Stoll et al., 2017).
However, the relationships between these system characteristics and resilience
are not necessarily linear or unidirectional. For example, increased connectivity could
decrease the resiliency of SESs due to lack of local control and decentralization
(Janssen et al., 2006). Specifically, rapid propagation of disturbances can occur in highly
connected systems (Biggs et al., 2012). In fishing dependent communities this may
mean that harvesting many species creates a relationship between seafood types where
there was no ecological relationship between them before (Fuller et al., 2017). Thus,
management decisions made for one seafood type could inadvertently impact many
seafood types in highly connected portfolios due to serial depletion (Armstrong et al.,
1998; Karpov et al., 2000). In addition, decentralization could decrease resiliency and
adaptive capacity in times of change when effective coordination of actors and resources
may be needed but there is no coordination of effort (Bodin et al., 2006).
Resilience and diversity also do not associate in a linear relationship. Higher
levels of diversity are costly in terms of system complexity and inefficiencies (Biggs et
al., 2012), which can further stagnate a system with no centralized effort. Although
diversity is important for SES resilience, functional redundancy is another important
system characteristic (Biggs et al., 2012), especially in a fisheries context where
functional roles of seafood types might have profound impacts on ecosystem function
21
(Bellwood, Hoey, & Choat, 2003). Therefore, there are trade-offs and uncertainties
associated with connectivity and diversity which makes it challenging to infer which
mechanism is dominant and how overall SES resilience is impacted.
Shifts in ɬaʔəmɛn harvest and consumption portfolios provide insight into the
influence of diversity and connectivity on resilience and offer opportunities to adapt to
the benefit of ecosystem health and community well-being. However, this is a complex
system with multiple mechanisms enhancing and detracting from resilience, many of
which are perceived as important in shifting in harvest and consumption portfolios
(Figure 4). Thus, understanding the underlying dynamics driving the system is helpful for
decision-making to ensure a resilient community in a Tla’amin Nation context.
Recommendations for adaptation opportunities in a Tla’amin Nation context
“in the summer time I would always go out on the canoe with my mother to get salmon and even then my mother told me that it won’t always be
like this” - Doreen Point
Resilient fishing communities are better able to adapt to future disturbances,
maintain their food and nutritional security and their cultural well-being. As such, our
results help inform future alternative adaptation strategies that have both local and
global relevance. Because we found no evidence that perceived importance of drivers
differed among respondents, regardless of their age, sex, occupation or boat ownership,
a community versus an individual approach to adaptation is likely more appropriate for
Tla’amin Nation future adaptations, and perhaps can be broadly considered among other
coastal Indigenous communities.
“we always fished and there has always been fish, we traditionally
managed our own [fisheries]” – Scott Galligos
Adaptation strategies should be tailored to specific SES and reflect local
characteristics, such as cultural norms and values (Andrachuk & Armitage, 2015;
Rotarangi & Stephenson, 2014), social networks (M. Barnes et al., 2017; Bodin, 2017),
politics (Gelcich et al., 2010) and place-specific environmental characteristics (Olsson et
al., 2006). Given knowledge from community experts and drawing on resilience theory,
our results suggest that adaptation strategies fostering knowledge transfer to younger
generations, and decentralizing natural resource management authority to local scales
22
would support resilience in this system. While climate change was perceived an
important driver of change, it was not ranked as most important, in contrast to the
majority of academic literature (Barange et al., 2014; Rudd, 2014; Savo, Morton, &
Lepofsky, 2017; Weatherdon et al., 2016). This is likely due to the magnitude of other
local stressors that impact ɬaʔəmɛn people’s daily lives, such as no longer being able to
dig clams in front of the village due to contamination closures. Furthermore, it is difficult
to observe long term, incremental climate trends, especially if experts are not old enough
to benefit from a longer time horizon. As such, future adaptation should embrace local
knowledge of perceived important problems, in tandem with evidence-based decision
making, if proposed management solutions are to be successfully implemented at the
local level (Bennett, 2016; Salomon et al., 2018).
Finally, our results embedded within ɬaʔəmɛn knowledge can inform how to best
serve community health in an Indigenous context. By linking drivers of change that
impact both harvest and consumption of individuals and the broader ɬaʔəmɛn
community, our results provide a more comprehensive understanding of disturbances
impacting multiple levels of community health. This can inform and assist Indigenous
peoples in control of their own health evaluations (Donatuto, Campbell, & Gregory,
2016). When planning for the future, Indigenous perspectives of all important drivers of
change are essential to consider for successful adaptation strategies for healthy
communities (Cisneros-Montemayor, Pauly, Weatherdon, & Ota, 2016; Donatuto et al.,
2016).
Advancing Resilience Theory
Our seemingly paradoxical results provide an opportunity to examine novel
mechanisms of resilience, where diversity and connectivity can function simultaneously
in opposing directions. Furthermore, we gathered expert knowledge to illuminate
dominant drivers of change and social-ecological mechanisms impacting the system to
relate them to overall resilience. A strong understanding of changes in SESs and local
perceptions of key disturbances causing these changes, and how they impact system
characteristics that confer or erode SES resilience, can form the basis of local strategies
to maintain food security and cultural well-being while adapting to various futures in
ecologically sustainable and socially just ways.
23
Figures
24
25
Figure 1. ɬaʔəmɛn harvest portfolios for pre and post 1980. Entire harvest portfolios (A,B) and core harvest portfolios (C,D) are shown. Cores were determined by being nodes with greater than or equal to the mean number of links in the network. Pre 1980 is comprised of 31 seafood types and represents 14 harvesters, whereas post 1980 is comprised of 28 seafood types and represents 17 harvesters. Node size represents the mean relative abundance, links between nodes represent at least one respondent reported harvesting both seafood types, and the layout of the network is represented with the Fruchterman-Reingold Algorithm*
*The Fruchterman-Reingold Algorithm is a force-directed layout algorithm. The idea of a force directed layout algorithm is to consider a force between any two nodes. In this algorithm, the nodes are represented by steel rings and the edges are springs between them. The attractive force is analogous to the spring force and the repulsive force is analogous to the electrical force. The basic idea is to minimize the energy of the system by moving the nodes and changing the forces between them (Csárdi & Nepusz, 2019).
26
27
Figure 2. ɬaʔəmɛn consumption portfolios for pre and post 1980. Entire consumption portfolios (A,B) and core consumption portfolios (C,D) are shown. Cores were determined by being nodes with greater than or equal to the mean number of links in the network. Pre 1980 is comprised of 35 seafood types and represents 14 respondents, whereas post 1980 is comprised of 32 seafood types and represents 21 respondents. Node size represents the mean relative abundance, links between nodes represent at least one respondent reported consuming both seafood types, and the layout of the network is represented with the Fruchterman-Reingold Algorithm*
* The Fruchterman-Reingold Algorithm is a force-directed layout algorithm. The idea of a force directed layout algorithm is to consider a force between any two nodes. In this algorithm, the nodes are represented by steel rings and the edges are springs between them. The attractive force is analogous to the spring force and the repulsive force is analogous to the electrical force. The basic idea is to minimize the energy of the system by moving the nodes and changing the forces between them (Csárdi & Nepusz, 2019).
28
Figure 3. Changes in portfolio composition (i.e. standardized degree centrality) and diversity (i.e. species richness) of harvest and consumption portfolios over time. Degree standardized degree centrality has significantly increased over time (A) while species richness decreases although the results are not significant (B). ****p<0.0001, *p<0.05
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Harvest Consumption Harvest Consumption
29
Figure 4. Mean ranked perceived importance of each pre-identified factor for driving changes in food fish harvest and consumption over the last several decades. There is no significant difference in perceived importance of factors driving changes between harvest and consumption.
30
Tables
Table 1. Respondents' qualitative reasons for changes in the harvest and
consumption of traditional seafoods, derived from an inductive analysis of themes.
Factor driving change
Reported percent
Description Observation (representative quote)
Environmental change
42% Changes in the marine environment including climate change, warming waters, red tide, etc.
“Red tide is more abundant these days compared to way back when. It seems like you can’t go and pick oysters or harvest clams like you used to back in the day, even in a warm spell. Red tide is always here.” – Bud Louie
Over harvesting 33% Over exploitation of marine resources (commercial, sport, FSC)
“Only harvest what you need, hurts me to see people fish too much and then waste it” – R05
Access 25% Factors allowing or limiting access which includes private property, boats, permit cards
“My dad had a boat and was always out getting something. I don’t have a boat. Boat motor and trailer is a big thing for a lot of people.” – Denise Smith
Governance barriers
25% Barriers to decision making power with other governing bodies (e.g. DFO) and within own self-governing institution
“I was on council and they opened up the herring and that decimated the whole run. We fought with DFO ... We have the traditional knowledge to prove that they always spawn here. It was always about protecting their own behind.” – R04
Costs 21% Economic cost of practicing traditional seafoods (e.g. boat expenses, cheaper grocery store food, etc.)
“Back in the day is wasn’t expensive b/c people went by dugout and would walk up the river. Didn’t cost anything just time and effort.” – Scott Galligos
Change in diet 38% Increased western food consumption
“You don’t have to go fishing anymore to provide for your family… food comes from the grocery store… that just wasn’t in the cards when I was a child.”- Roy Francis
Modernization 50% Modernization of community resulting in a change of traditional values
“Times are just changing. In the past people were dependent on the ocean and the food that came from it.” - Elsie Paul
Pollution 25% Pollution from local sources (i.e. sewage and mill)
“fecal coliform was the biggest issue in the past, we [Tla’amin Nation] had tests done and it wasn’t their sewage that was the sustained source.”- Eugene Louie
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Factor driving change
Reported percent
Description Observation (representative quote)
Predation 21% Competition for fish with other predators, mainly pinnipeds
“I think there is less and less stuff that you can actually go out and harvest anymore. Actual abundance out there [has decreased]. There are a lot of reasons, pollutions, predation … they put the moratorium on them [seals] years ago and their numbers are huge. The sea lions don’t leave anymore, they just stay … they are taking fish right off the line.” – R04
Technology 4% Advancement of fishing technologies (e.g. fish finders)
“technology has changed… the technology is incredible… I have fish finders and you can tell how many fish are on the reef right below you… I am there with a dozen other boats with the same technology I have so the fish stand less of a chance.” – Roy Francis
Knowledge 13% Knowledge is not being transferred to younger generations
“my brother and I would go and catch herring and drop it off door to door but some people just didn’t know what to do with the herring, there is a loss of knowledge” – Roy Francis “the elders that are passing on… those values are not instilled to the youth and that art gets lost” – Lee George
Community dependence
8% Dependence on the Nation to provide food fish allocation
“I think we have done things with the goal of being helpful, like we will go out and get communal harvest…. We will bring salmon door to door with the meaning of being a good thing…. We have unintentionally created a bad thing. There is a dependence on coming fish coming to the door… I don’t think that is necessarily a good thing. I think a better idea would be to encourage people to go out there and do their own harvest” – Roy Francis
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Appendix Supplementary Figures and Tables
Figure A1. Study Area - Research was conducted in collaboration with the Tla’amin Nation which is located on the west cost of British Columbia, Canada.
Table A1. Sample size of respondents and number of seafood types in each harvest and consumption portfolios for pre and post 1980 time periods.
Time period
Decades included Portfolio type
Number of respondents
Number of seafood type
Pre 1980 1940-1950, 1950-1960, 1960-1970, 1970-1980
Harvest 14 31
Pre 1980 1940-1950, 1950-1960, 1960-1970, 1970-1980
Eat 14 35
Post 1980 1980-1990, 1990-2000, 2000-2010, 2010-2018
Harvest 17 28
Post 1980 1980-1990, 1990-2000, 2000-2010, 2010-2018
Eat 21 32
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Table A2. Seafood types’ common name(s) with associated Latin scientific name(s) and ɬaʔəmɛn name(s). Some seafood types have grouped similar species together (e.g. clams) since they can be harvested together easily. Others are separate (e.g. salmon species) due to the cultural importance of each individual species. ɬaʔəmɛn words were provided by ɬaʔəmɛn elders who have given their knowledge so that the language is not forgotten*.
Common name(s) Scientific name(s) ɬaʔəmɛn name(s)
Northern abalone Haliotis kamtschatkana -
Black cod Anoplopoma fimbria -
Chinook salmon Oncorhynchus tshawytscha θat̓ᶿəm
Chum salmon Oncorhynchus keta ƛoχʷay
Clams - Butter, little neck, manila, cockle
Saxidomus giganteus, Protothaca staminea, Venerupis philippinarum, Clinocardium nuttallii
χəʔa, ɬoɬmom, ƛiyʔam
Coho salmon Oncorhynchus kisutch χɛyt̓ᶿɛqʷ
Crab - Red rock, Dungeness crab
Cancer productus, Metacarcinus magister χɛχyɛq̓
Spiny dogfish Squalus suckleyi kʷač̓
Eulachon Thaleichthys pacificus t̓ᶿəmtəq
Flounder and sole Paralichthyidae, Pleuronectidae papgay
Pacific geoduck Panopea abrupta -
Green sea urchin Strongylocentrotus droebachiensis ʔəptən
Pacific halibut Hippoglossus stenolepis p̓agi
Pacific herring Clupea pallasii pallasii ɬagət
Pacific herring roe Clupea pallasii pallasii χawχɛk̓ʷum
Kelp greenling Hexagrammos decagrammus -
Lingcod Ophiodon elongatus t̓ᶿoχo
Lingcod eggs Ophiodon elongatus k̓ʷuʔəmk̓ʷum
Pacific blue mussels Mytilus trossulus saʔma
Northern giant pacific octopus Enteroctopus dofleini taqʷə
Pacific cupped oyster Crassostrea gigas ƛoχƛoχ
Pacific tomcod Microgadus proximus -
Perch Embiotocidae -
Pink Salmon Oncorhynchus gorbuscha kʷətɛčɩn
Spot prawn Pandalus platyceros kikɛʔəqəɬ
Purple sea urchin Strongylocentrotus purpuratus -
Red sea urchin Mesocentrotus franciscanus maseqʷ
Rockfish - Tiger, Yellowmouth, China, Yelloweye, Copper, Yellowtail, etc. rockfish
Sebastes spp. -
Pacific sardine Sardinops sagax -
Scallops - Spiny, Rock scallop Chlamys hastata, Crassadoma gigantea -
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Common name(s) Scientific name(s) ɬaʔəmɛn name(s)
Red sea cucumber Parastichopus californicus ʔələs
Harbour seal Phoca vitulina ʔasxʷ
Seaweed and kelp Seaweed and kelp species in area ƛəqstən, kʷumt
Longnose skate Raja rhina -
Sockeye salmon Oncorhynchus nerka θəqay
*Retrieved from: https://www.firstvoices.com/explore/FV/sections/Data/Salish/Northern%20Salishan/Sliammon
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Table A3. Factors driving changes in food fish harvesting and consumption in ɬaʔəmɛn traditional territory. Each factor is accompanied by a description and rationale citations for our inclusion in asking experts questions regarding perceived importance of the factors in driving changes in the area.
Factor Description Rationale citation
Change in economic market
Change in the supply and demand of seafood, expenses and costs of fishing (price of fish and for going out and getting fish – e.g. boat gas and boat insurance)
Frawley, Finkbeiner, & Crowder, 2019; Kaplan-hallam, Bennett, & Satter, 2017; Turner et al., 2008
Commercial overharvesting
Over fishing from the commercial sector which includes members of the Tla’amin Nation that participate commercially – e.g. clam diggers
pers. comm. Hegus Clint Williams; Paul et al., 2014
Climate change Change in the marine environment – e.g. changing water temperatures, change in ocean acidification, red tides, etc.
Cheung et al., 2015; Weatherdon et al., 2016
Your ability to get a permit card
The ability to get a permit card at the Governance House acting as a barrier
Pers. comm. Denise Smith, Lori Wilson
Your ability to get access to a harvest area
The ability for one to get access to a harvest area acting as a barrier – e.g. require a boat or need to go through private property
Pers. comm. Scott Galligos; Fediuk & Thom, 2003; Joyce & Canessa, 2009
Change in traditional diet
Change in the traditionally consumed diet in the territory – e.g. increased western food availability
Fediuk & Thom, 2003; Kuhnlein & Receveur, 1996; Turner et al., 2008
Ocean pollution Pollution (specifically water contamination and mill contamination) of marine waters and intertidal zones – e.g. clam beaches closed. We are not asking about plastic pollution which is known as a convenient but distracting truth (Stafford & Jones, 2019)
Fediuk & Thom, 2003; Lewitus et al., 2012; Turner et al., 2008
Barriers to decision making power
Barriers to having authority to make decisions of resources in Tla’amin traditional territory – e.g. having a seat at the table with DFO
Ban & Frid, 2018; Fediuk & Thom, 2003; Jones et al., 2017; Joyce & Canessa, 2009; Klain, Beveridge, & Bennett, 2014; Turner et al., 2008; von der Porten et al., 2016
Intergenerational knowledge loss
Traditional knowledge not being transferred to youth and younger generations
Barnes, 2008; Fediuk & Thom, 2003; Harper et al., 2018; Turner et al., 2008
Change in people’s taste
Change in people’s food preferences Beaudreau et al., 2018; Paul et al., 2014
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Table A4. Beta regression output of the effect of time on the relative abundance of each harvested seafood type ordered by percent change.
Seafood Type Estimate Std. Error Z value P value % change
Pacific herring -0.81 0.15 -5.35 0.00000 -37.55
Pacific herring roe -0.66 0.17 -3.94 0.00008 -31.08
Chum salmon -0.26 0.18 -1.44 0.15045 -14.46
Lingcod eggs -0.40 0.13 -3.01 0.00264 -14.40
Red sea urchin -0.32 0.13 -2.53 0.01147 -11.11
Green sea urchin -0.27 0.11 -2.38 0.01739 -8.93
Pink Salmon -0.17 0.22 -0.76 0.44658 -8.30
Perch -0.26 0.06 -4.23 0.00002 -7.94
Flounder -0.24 0.12 -2.03 0.04260 -7.86
Harbour seal -0.25 0.06 -4.44 0.00001 -7.85
Black cod -0.24 0.09 -2.73 0.00633 -7.43
Red sea cucumber -0.24 0.04 -5.81 0.00000 -7.41
Pacific geoduck -0.23 0.07 -3.35 0.00081 -7.06
Spiny dogfish -0.20 0.02 -8.42 0.00000 -6.24
Scallops - Spiny, Rock scallop -0.20 0.08 -2.52 0.01169 -6.18
Northern giant pacific octopus -0.19 0.08 -2.42 0.01560 -5.89
Pacific tomcod -0.17 0.16 -1.10 0.27010 -5.73
Coho salmon -0.12 0.17 -0.72 0.47320 -5.42
Chinook salmon -0.12 0.18 -0.65 0.51414 -5.22
Purple sea urchin -0.15 0.11 -1.30 0.19485 -4.65
Kelp greenling -0.14 0.08 -1.70 0.08834 -4.44
Pacific blue mussels -0.10 0.12 -0.82 0.41177 -3.29
Clams - Butter, little neck, manila, cockle
-0.05 0.21 -0.26 0.79113 -2.85
Seaweed and kelp -0.08 0.11 -0.78 0.43819 -2.66
Crab - Red rock, Dungeness crab -0.05 0.17 -0.28 0.78293 -1.89
Pacific halibut -0.04 0.14 -0.28 0.78120 -1.26
Rockfish - Tiger, Yellowmouth, China, Yelloweye, Copper, Yellowtail, etc. rockfish
0.01 0.16 0.08 0.93852 0.54
Sockeye salmon 0.07 0.19 0.36 0.72218 2.97
Lingcod 0.10 0.19 0.54 0.58621 4.72
Pacific cupped oyster 0.21 0.21 1.00 0.31823 10.10
Spot prawn 0.33 0.20 1.66 0.09751 11.63
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Table A5. Beta regression output of the effect of time on the relative abundance of each consumed seafood type ordered by percent change.
Seafood Type Estimate Std. Error Z value P value % change
Pacific herring -0.80 0.13 -6.25 0.00000 -35.31
Lingcod eggs -0.69 0.12 -5.70 0.00000 -24.97
Pacific herring roe -0.41 0.11 -3.70 0.00021 -18.55
Red sea urchin -0.45 0.15 -2.96 0.00311 -16.14
Pink Salmon -0.34 0.14 -2.48 0.01314 -15.97
Green sea urchin -0.47 0.13 -3.66 0.00025 -15.70
Harbour seal -0.49 0.06 -8.72 0.00000 -15.37
Pacific tomcod -0.41 0.17 -2.43 0.01518 -14.64
Coho salmon -0.31 0.11 -2.72 0.00654 -14.46
Perch -0.47 0.05 -9.21 0.00000 -14.40
Black cod -0.45 0.08 -5.53 0.00000 -14.24
Longnose skate -0.46 0.04 -11.72 0.00000 -14.05
Spiny dogfish -0.44 0.04 -10.24 0.00000 -13.61
Clams - Butter, little neck, manila, cockle
-0.27 0.09 -2.84 0.00449 -13.16
Red sea cucumber -0.43 0.05 -8.40 0.00000 -13.14
Flounder -0.40 0.10 -4.08 0.00004 -12.99
Pacific geoduck -0.41 0.06 -6.94 0.00000 -12.79
Purple sea urchin -0.38 0.10 -3.69 0.00023 -11.96
Eulachon -0.35 0.11 -3.15 0.00164 -11.42
Kelp greenling -0.34 0.08 -4.29 0.00002 -10.55
Northern abalone -0.33 0.08 -4.21 0.00003 -10.14
Northern giant pacific octopus -0.32 0.10 -3.07 0.00212 -10.07
Chum salmon -0.18 0.11 -1.69 0.09118 -9.43
Rockfish - Tiger, Yellowmouth, China, Yelloweye, Copper, Yellowtail, etc. rockfish
-0.19 0.11 -1.64 0.10147 -8.59
Chinook salmon -0.20 0.15 -1.31 0.18996 -8.46
Pacific sardine -0.23 0.13 -1.84 0.06531 -7.53
Seaweed and kelp -0.23 0.13 -1.77 0.07707 -7.44
Lingcod -0.05 0.15 -0.33 0.74275 -2.07
Sockeye salmon -0.04 0.10 -0.37 0.71424 -1.59
Pacific blue mussels -0.02 0.14 -0.13 0.89395 -0.64
Crab - Red rock, Dungeness crab 0.03 0.11 0.28 0.78068 1.19
Scallops - Spiny, Rock scallop 0.07 0.12 0.60 0.54859 2.35
Pacific cupped oyster 0.07 0.13 0.53 0.59778 2.83
Pacific halibut 0.48 0.10 4.97 0.00000 16.25
Spot prawn 0.61 0.12 5.12 0.00000 21.78
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Table A6. Strength of evidence for alternative models explaining the perceived importance in drivers of change for traditional seafood harvest and consumption among 23 and 22 experts, respectively.
Model N K AICc AICc LL
Harvest Ranked Importance Driver 23 12 733.41 0 -353.98
Driver*Gender 23 22 737.16 3.75 -344.12 Driver*Age 23 22 746.62 13.22 -348.85 Driver*Boat 23 22 748.15 14.75 -349.62 Driver*Employment 23 22 750.42 17.01 -350.75
Consumption Ranked Importance Driver 22 12 697.80 0 -336.14
Driver*Gender 22 22 706.88 9.08 -328.86 Driver*Age 22 22 713.29 15.49 -332.06 Driver*Boat 22 22 713.46 15.66 -332.15 Driver*Employment 22 22 714.81 17.01 -332.82
Notes: Likelihoods are specified for each model. K, the number of estimable parameters in the model; AICc, Akaike information criterion corrected for sample size; ΔAICc, change in AICc; LL, log- likelihood
Figure A2. Shown above are species accumulation curves for each portfolio. (A) Pre 1980 harvesting, (B) Post 1980 harvesting, (C) Pre 1980 consumption, (D) Post 1980 consumption. Shaded area shows the 95% confidence intervals. The curves were made with the vegan package in R, specifically the specaccum() function (Gotelli & Colwell, 2001).
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Figure A3. Bootstrapped standardized degree centrality for harvest (A) and consumption (B) portfolios with varying proportions of nodes (i.e. seafood types). All bootstrapped comparisons of degree centrality show a significant effect of time and an increasing trend. Nodes were bootstrapped in increased proportion (0.5, 0.6, 0.7, 0.8, 0.9, 1.0) of total number of seafood types for 100 iterations without replacement.
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Figure A4. Our data (A) compared to portfolio link sensitivity analysis (B) both show a significant effect of time and increasing degree centrality trend on harvest and consumption portfolios. Bootstrapped degree centrality data where 80% of the links is sampled without replacement for 100 iterations.