gvi jalova expedition phase report october-december 2011 114

Global Vision International 2011 Report Series No. 004

GVI Costa RicaJalova, Parque Nacional Tortuguero

Quarterly Report 114 October December 2011GVI Costa Rica (Jalova) Programme Report 114 Submitted in whole to GVI Submitted in part to The Ministry of Environment and Energy of Costa Rica (MINAET)

Produced by Richard Phillips Field Coordinator Alexander Mead Field Staff Loraine Grant Field Staff Benjamin Barca Field Staff James Guilder Field Staff And

Kevin Wells Kylie Wright Sarah Bird Natasha De Bondi Leo Keedy Kate Valencia Helen Maconachie Zachary Halter Yannie Cheung Aaron Faunch Kristen Byrne Josefin Ljungblom Thomas Edwards Elizabeth Ames Noel Lohmann

Field Staff Intern Intern Intern Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer

Zachary Moore-Hopkins Jennifer Sunnfors Li von Sydow Angela Fuchs Greta Columbi Melissa Eagen Jennifer Harris Zoe Schonfeld Karin van der Zwan Rachael Downes Garrett Steed Evelina Barman William Fitting Daniel Jolly

Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer Volunteer

Edited by Stephen Meyer Country Director Christina Harnois Logistics Coordinator

GVI Costa Rica (Jalova) Email: [email protected] Web page: http://www.gvi.co.uk and http://www.gviusa.com

Executive SummaryThe eighth 10-week phase of the Costa Rican GVI Jalova Programme has now been completed. The programme has continued to work towards the gathering of important environmental scientific data whilst working with local, national and international partners. The following projects have been run during Phase 114 (October - December 2011): Canal Bird Population Study Jaguar Camera Trapping in Tortuguero National Park (TNP) Jaguar Predation on Marine Turtles. Incidental Species and Diversity Assessment Biodiversity Assessment Project Marine Turtle Monitoring Beach Clean

GVI Jalova, Parque Nacional Tortuguero, October December 2011

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Table of ContentsExecutive Summary ............................................................................................................. i Table of Contents ................................................................................................................ ii List of Figures .................................................................................................................... iii List of Tables ..................................................................................................................... iv 1. Introduction ................................................................................................................ 5 2. Canal Bird Population Study ..................................................................................... 6 2.1 Introduction ..................................................................................................... 6 2.2 Aim ................................................................................................................. 7 2.3 Methodology ................................................................................................... 7 2.4 Results ............................................................................................................. 7 2.5 Discussion ..................................................................................................... 14 3. Jaguar Camera Trapping Project .............................................................................. 17 3.1 Introduction ................................................................................................... 17 3.2 Aim ............................................................................................................... 17 3.3 Methodology ................................................................................................. 18 3.4 Results ........................................................................................................... 18 3.5 Discussion ..................................................................................................... 21 4. Jaguar Predation of Marine Turtles.......................................................................... 23 4.1 Introduction ................................................................................................... 23 4.2 Aim ............................................................................................................... 24 4.3 Methodology ................................................................................................. 24 4.4 Results ........................................................................................................... 24 4.5 Discussion ..................................................................................................... 27 5. Incidental Species Study .......................................................................................... 30 5.1 Introduction ................................................................................................... 30 5.2 Aim ............................................................................................................... 30 5.3 Methodology ................................................................................................. 30 5.4 Results ........................................................................................................... 31 5.5 Discussion ..................................................................................................... 38 6. Biodiversity Assessment Project.............................................................................. 45 6.1 Introduction ................................................................................................... 45 6.2 Aim ............................................................................................................... 45 6.3 Methodology. ................................................................................................ 45 6.4 Results ........................................................................................................... 46 6.5 Discussion ..................................................................................................... 52 7. Marine Turtle Monitoring ........................................................................................ 55 7.1 Introduction ................................................................................................... 55 7.2 Methodology ................................................................................................. 55 7.3 Results ........................................................................................................... 55 8. Beach Clean ............................................................................................................. 56 8.1 Introduction ................................................................................................... 56 8.2 Methodology ................................................................................................. 56 8.3 Results ........................................................................................................... 56

GVI Jalova, Parque Nacional Tortuguero, October December 2011

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8.4 Discussion ..................................................................................................... 56 9. References ................................................................................................................ 57 10. Appendices ............................................................................................................... 59 Appendix A. Canal Bird Population Study Methodology ................................................ 59 Appendix B: List of Study Bird Species ........................................................................... 63 Appendix C: Jaguar Camera Trapping Project Methodology........................................... 64 Appendix D: Jaguar Predation of Marine Turtles Study Methodology ............................ 68 Appendix E: Incidental Study Species Methodology ....................................................... 72 Appendix F: Species list indicating the percentage of days seen in Amphibia, Aves, Mammalia and Reptilia found throughout zones A F between phases 114 and 104. .... 76 Appendix G: Biodiversity Assessment Methodology....................................................... 85 Appendix H: Incidental Species List ................................................................................ 90

List of FiguresFigure 2-1 Number of canal bird species per canal ............................................................... 8 Figure 2-2 Number of canal bird records per canal ............................................................. 10 Figure 2-3 Number of canal incidentals species, records per canal ..................................... 13 Figure 3-1 This bar chart illustrates the times at which all individual captures were taken during Phase 114. Identified and non-identified jaguars were included in this graph ......... 20 Figure 4-1 Spatial Distribution of Jaguar Presence, Predated Turtles and Turtle Nests ...... 25 Figure 4-3 This boxplot shows the different spread of data between jaguar presence close to human presence (1) and further from human presence (2). ................................................. 26 Figure 4-2 Number of Green tracks, predated turtles and jaguar presence for the 9 surveys .............................................................................................................................................. 26 Figure 5-1 Total percent of species recorded per zone ........................................................ 32 Figure 5-2 Distribution of records per class across zones ................................................... 33 Figure 5-3 Distribution of Amphibia records per zone ........................................................ 34 Figure 5-4 Distribution of Aves records per zone ............................................................... 35 Figure 5-5 Distribution of Mammalia records per zone ...................................................... 35 Figure 5-6 Distribution of Reptilia records per zone ........................................................... 36 Figure 6-1 Average number of species and records per transect ......................................... 48 Figure 6-2 Total number of species recorded by class ........................................................ 48 Figure 6-3 Average number of records by class .................................................................. 50 Figure 6-4 Average number of Aves, Mammalia and Reptilia records per transect by class .............................................................................................................................................. 51 Figure 6-5 Average number of Amphibia records per transect by class .............................. 51

GVI Jalova, Parque Nacional Tortuguero, October - December 2011

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List of TablesTable 2-1 Overall canal bird data phase 114 ...................................................................... 8 Table 2-2 Species Presence/Absence per Canal .................................................................... 9 Table 2-3 Species Frequency by Canal ................................................................................ 11 Table 2-4 Max and Mean number of each species recorded per canal (n=number of surveys) ................................................................................................................................ 12 Table 2-5 Overall canal incidentals data phase 114.......................................................... 13 Table 2-6 Overall canal usage data phase 114 .................................................................. 14 Table 3-1 Jaguar Capture and Recaptures ........................................................................... 20 Table 5-1 Species recorded for the first time in 2011 .......................................................... 31 Table 5-2 Total number of species recorded per zone. ........................................................ 32 Table 5-3 Total number of dates recorded per zone from a maximum of 70 days .............. 33 Table 5-4 Comparison of total number of species recorded per zone. X denotes no significance between zones. P denotes P-value after analysis ............................................. 37 Table 5-5 Comparison of total number of species recorded per class. X denotes no significance between class. P denotes P-value after analysis .............................................. 38 Table 8-1 Selection of beach clean tallies............................................................................ 56 Table 10-1 Transect names, distances and time allowances ................................................ 85

GVI Jalova, Parque Nacional Tortuguero, October - December 2011

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1.IntroductionThe Coastal Rainforest Conservation Programme at the Jalova Biological Station in Tortuguero National Park, Costa Rica has now completed its eighth phase (eight times 10 weeks). For the purpose of this report, research phases are named following the last 2 digits of the year and then 1 for January to March, 2 for April to June, 3 for July to September and 4 for October to December. This report summarizes the data collected from October to December 2011, phase 114.

Since its initiation the programme has collected a considerable amount of scientific data for all its projects. This data has been submitted to the partner organisations and will go towards planning future research areas and meeting current project aims.

This data has been summarized in this report. To draw further conclusions some annual reports have been created for projects where the data set is large enough. These can be read upon request.

GVI - Jalova, Parque Nacional Tortuguero, April - June 2011

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2.Canal Bird Population Study2.1 Introduction

Mesoamerica is a very important hotspot for biological diversity (Myers et. al., 2000). With over 830 species of avifauna alone, Costa Rica is a very rich country for nature (Stiles & Skutch, 1989). One of the reasons for this richness is the array of habitats available in such a small space. These include two very different coastlines, highland and lowland forests, forest swamps, marshes, rivers, lagoons, and subalpine pramos (Stiles & Skutch, 1989). The aquatic environment is of major importance to the tourism industry and ecology of the Tortuguero area. This habitat is being increasingly utilized as tourism in the Tortuguero area is increasing. It is expected that this use will, in time, have an impact on the avian population it supports. Growing concerns about the status of birds in the rainforests of Costa Rica have led to the establishment of long-term monitoring programmes. The nature of Costa Ricas birdlife has meant that it has been a popular location to study behaviour and diversity for many years. Much of this focus is directed towards migratory birds, neglecting research on resident species. The Canal Bird Monitoring Programme was established to help fill this gap. The project was initially set up to quantify diversity and abundance of the species that live and breed in the area of Caribbean Lowland Rainforest around Estacin Biolgica Cao Palma (EBCP), 7km North of Tortuguero National Park. It now operates along the southern edge of Tortuguero National Park in the vicinity of Jalova (24km South of Tortuguero). The EBCP Resident Bird Project monitoring survey began in July 2005, developing in recent years into the current incarnation, which is still ongoing. Further collection of data is important in order to establish reliable population trends for local bird species. In 2010 it was necessary to relocate the survey to the current location due to the demands of the GVI Costa Rica expedition. The GVI protocol is modified from the original protocol created by Steven Furino of Waterloo University, Canada. Modifications to the protocol were made so that data collectors with minimal field experience are able to collect high quality data. This has involved reducing the number of species and study areas; as well as limiting the amount of technical data collected on species.


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2.2

Aim

This research programme intends to collect data that will help researchers examine longterm changes in specific bird populations. The specific aims of the project are 1) to identify study species use of the study areas, 2) monitor long-term changes in use of these areas, and 3) to aid in the collection of both resident and migratory avian population data sets for wider public use. 2.3 Methodology

Changes to the project for phase 114 include a change of canal. The canal Sirena has been removed due to recording consistently low results and Cao Negro added due to its potential for recording more results. In addition, all canals have been doubled in length from 2km to 4km. By expanding the survey area, the project should be able to gather many more results. The methodology for the remainder of the survey has remained constant since the production of the previous report, where the methodology is mentioned in full. For further details of the methodology used, please see Appendix A.

2.4

Results

A total of 26 surveys have been completed throughout the course of phase 114. These surveys collected 1186 individual seen or heard records, comprising of 22 of the target canal bird species (Appendix B). A canal specific break down of the data gathered can be observed in table 2-1. Figure 2-1 illustrates that of the data collected, California and Sierpe Viejo recorded the most species; approximately double that of Cao Negro and Central. Figure 2-2 illustrates California recording far more individual records than the remaining canals, however, California did receive 6 more surveys than Sierpe Viejo and 7 more than Central due to the project not being able to reach these canals as the GVI boat was broken down. This potentially had a great effect on results. Sierpe Viejo and Cao Negro recorded a similar amount of individual records despite Cao Negro receiving 5 more surveys. Central recorded the lowest amount of species and records, although did receive the least amount of surveys. A canal specific breakdown of the presence or absence of each of the target species can be observed in table 2-2.


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Table 2-1 Overall canal bird data phase 114 Canal California Sierpe Viejo Cao Negro Central # of Surveys 10 4 9 3 # of Species 20 19 12 10 # of Records 820 161 141 64

Figure 2-1 Number of canal bird species per canal


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Table 2-2 Species Presence/Absence per Canal Species California Central Sierpe Viejo Cao Negro Agami Heron Amazon Kingfisher American Pygmy Kingfisher Anhinga Bare-throated Tiger-heron Belted Kingfisher Boat-Billed Heron Cattle Egret Gray-necked Wood-rail Great Blue Heron Great Egret Green Heron Green Ibis Green Kingfisher Green-and-rufous Kingfisher Limpkin Least Bittern Little Blue Heron Neotropical Cormorant Northern Jacana Purple gallinule Reddish Egret Ringed Kingfisher Rufescent Tiger-Heron Snowy Egret Sunbittern Sungrebe Tricoloured Heron White-throated Crake Yellow-crowned Night-heron N Y N Y Y Y Y Y Y Y Y Y Y Y N N N Y N Y Y N Y N Y N Y Y N Y N Y N Y Y N Y Y N N N Y N N N N N Y N Y N N Y N Y N N N N Y N Y N Y Y N Y Y N Y Y Y Y Y N N N Y N Y Y N Y N Y Y N Y Y Y N Y N Y Y N N Y N N Y Y Y Y N N N Y N N N N Y N Y N N N N Y N Y N Y Y Y Y Y Y Y Y Y Y Y N N N Y N Y Y N Y N Y Y Y Y Y Y Overall


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Figure 2-2 Number of canal bird records per canal

The data collected over phase 114 indicates that of the species recorded on the canals, the Amazon Kingfisher, Anhinga, Bare-throated Tiger Heron, Green Heron, Little Blue Heron, Northern Jacana and Snowy Egret are recorded most often; on average over 50% more often?across all canals. Canal specific species encounter frequencies can be observed in Table 2-3. The maximum number of individuals recorded in one survey over the entire survey period, as well as the mean number of individuals recorded over all surveys conducted can be observed in table 2-4. The species recording higher numbers are consistent with the species listed above.


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Table 2-3 Species Frequency by Canal Species California Central Sierpe Viejo Cao Negro Agami Heron Amazon Kingfisher American Pygmy Kingfisher Anhinga Bare-throated Tiger-heron Belted Kingfisher Boat-Billed Heron Cattle Egret Gray-necked Wood-rail Great Blue Heron Great Egret Green Heron Green Ibis Green Kingfisher Green-and-rufous Kingfisher Little Blue Heron Least Bittern Limpkin Neotropical Cormorant Northern Jacana Purple Gallinule Reddish Egret Ringed Kingfisher Rufescent Tiger-Heron Snowy Egret Sunbittern Sungrebe Tricoloured Heron White-throated Crake Yellow-crowned Night-heron 0% 90% 0% 100% 100% 10% 10% 50% 20% 70% 20% 100% 50% 70% 0% 100% 0% 0% 0% 100% 10% 0% 20% 0% 100% 0% 60% 40% 0% 80% 0% 100% 0% 33.3% 33.3% 0% 0% 33.3% 0% 0% 0% 33.3% 0% 0% 0% 100% 0% 0% 0% 100% 0% 0% 33.3% 0% 33.3% 0% 0% 0% 0% 33.3% 0% 50% 0% 100% 50% 0% 25% 50% 0% 25% 100% 75% 50% 50% 0% 100% 0% 0% 0% 100% 25% 0% 75% 0% 75% 25% 0% 100% 50% 75% 0% 33.3% 0% 11.1% 77.7% 0% 0% 33.3% 0% 0% 11.1% 55.5% 88.8% 66.6% 0% 11.1% 0% 0% 0% 0% 0% 0% 11.1% 0% 22.2% 0% 0% 0% 0% 100% 0% 68% 0% 61% 65% 3% 9% 42% 5% 24% 33% 66% 47% 47% 0% 78% 0% 0% 0% 75% 9% 0% 35% 0% 58% 6% 15% 35% 13% 72% Average


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Table 2-4 Max and Mean number of each species recorded per canal (n=number of surveys) Species Agami Heron Amazon Kingfisher American Pygmy Kingfisher Anhinga Bare-throated Tiger-Heron Belted Kingfisher Boat-billed Heron Cattle Egret Great Blue Heron Great Egret Green Heron Green Ibis Green Kingfisher Green and Rufous Kingfisher Gray-necked Wood-Rail Least Bittern Limpkin Little Blue Heron Neotropical Cormorant Northern Jacana Purple Gallinule Reddish Egret Ringed Kingfisher Rufescent Tiger-Heron Snowy Egret Sun Bittern Sungrebe Tricoloured Heron White-throated Crake Yellow-crowned Night-heron California (n=10) Max Mean 0 0 3 1.5 0 0 5 3.5 6 3.5 1 0.1 1 0.1 6 1.3 4 1.5 8 0.9 23 13.8 4 1.6 5 1.9 0 0 1 0.2 0 0 0 0 23 15.7 0 0 19 10.6 1 0.1 0 0 2 0.3 0 0 94 22.1 0 0 2 0.7 3 0.8 0 0 6 1.7 Sierpe Viejo (n=4) Max Mean 0 0 1 0.5 0 0 4 2.5 2 0.75 0 0 1 0.25 9 3 1 0.25 4 2.25 5 2.25 4 1.5 4 1.5 0 0 0 0 0 0 0 0 8 5.75 0 0 17 12.25 1 0.25 0 0 3 1.5 0 0 5 1.75 1 0.25 0 0 2 1.25 3 1 3 1.5 Cao Negro (n=9) Max Mean 0 0 2 0.44 0 0 1 0.11 3 1.22 0 0 0 0 6 1.33 0 0 1 0.11 2 0.66 8 3.11 5 1.44 0 0 0 0 0 0 0 0 1 0.11 0 0 0 0 0 0 0 0 1 0.11 0 0 3 0.55 0 0 0 0 0 0 0 0 11 6.44 Central (n=3) Max Mean 0 0 1 1 0 0 0 0.66 1 0.33 0 0 0 0 9 3 0 0 0 0 1 0.33 0 0 0 0 0 0 0 0 0 0 0 0 8 5.33 0 0 13 9.66 0 0 0 0 1 0.33 0 0 1 0.33 0 0 0 0 0 0 0 0 1 0.33


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Canal incidental data collected during the phase can be observed in table 2-5 and in figure 2-3. California recorded the most species and records, however Central and Sierpe Viejo did receive less surveys as stated previously.

Table 2-5 Overall canal incidentals data phase 114

Canal

Number of dates

Number of species

Number of records

California Cao Negro Central Sierpe Viejo Total Findings

10 9 3 4 26

30 24 8 17 49

225 142 64 46 477

Figure 2-3 Number of canal incidentals species, records per canal

GVI - Jalova, Parque Nacional Tortuguero, October - December 2011

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Canal usage data collected during phase 114 can be observed in table 2-6, with Cao Negro receiving the most boat usage. The lack of boats recorded on Sierpe Viejo and Central can also be attributed to the lower number of surveys.

Table 2-6 Overall canal usage data phase 114

Table 2-6 Overall canal usage data phase 114Canal Number of Surveys Number of boats recorded Number of surveys with no boats recorded California Sierpe Viejo Cao Negro Central 10 4 9 3 1 0 5 1 9 4 7 2

2.5

Discussion

The 26 canal bird surveys from phase 114 have provided further positive data on the canal bird populations of Tortuguero National Park; identifying 22 of the 30 target species and 1186 individual records. Comparing these figures to the same time in the previous year, phase 104, a very similar number of species (21) were recorded. The differences in species recorded being that phase 114 did not record the American Pygmy Kingfisher as in 104 but did record the Great Egret and Sunbittern which were not recorded in the previous year. Individual records were higher this year than last, with an additional 260 individual birdsodd choice of word sounds like a crime has been comited. This is likely to be due to the additional 5 surveys undertaken as well as carrying out surveys on two different canals, Cao Negro and Central whereas in phase 104 Sirena was surveyed, which in general provided low numbers of individual records. In addition, both California and Sierpe Viejo are 2km longer now compared to phase 104, therefore as expected results are higher.

California and Sierpe Viejo surveys continue to record the higher numbers of species than the other canals as has been the trend in previous years, recording 20 and 19 species GVI - Jalova, Parque Nacional Tortuguero, October - December 2011 Page 14

respectively, compared to Cao Negro (12 species) and Central (10 species), even with discrepancies in the numbers of surveys completed per canal.

Data collection on Sierpe Viejo and Central was hindered during the first five weeks of the phase due to the unavailability of the GVI boat and therefore a lower number of surveys were carried out on these canals. In addition, during the heavy rainfall of week 9 all canal surveys were suspended on health and safety grounds. An additional factor affecting surveys is the inaccessibility to the Sierpe Viejo canal of the Sierpe Viejo survey route; with the survey route itself only consisting of the Cao Negro and Cao Sierpe portions of the route. The potential result of this could be the absence of recording the Agami Heron which in the previous three phases has been recorded on the canal.

One exciting result gained in phase 114 is the recording of the uncommon Sunbittern on the Sierpe Viejo survey route. The bird was observed on the newly extended part of the survey route, on the Cao Negro portion before entering Cao Sierpe. This record is the first in the two year period of surveying the canals around the Jalova base area, although Sunbitterns have been spotted in the area previously on an incidental basis.

Incidental sightings records provided positive results on other species found in and around the canals; recording 49 species over 477 individual records. Californias records indicated the highest species diversity, recording 30 species. Cao Negro recorded slightly less with 24 species but was surveyed once less. Sierpe Viejo and Central recorded lower species numbers but were surveyed less as previously stated. A definite effect of the number of surveys is apparent due to results gained in the previous phase (113), Centrals recording 36 species after 6 surveys in comparison to 8 species in 3 surveys. In addition, 2 of the 3 surveys were carried out in constant rain, the rain potentially having an effect on the presence of animals.

Several notable sightings gained from the incidentals data included uncommon species such as; 1 Northern Tamandua on Cao Negro, 1 King Vulture on California, 2 Neotropical River Otters (1 on Sierpe Viejo and 1 on Cao Negro), 1 Great Curassow on California, 1 Masked Duck on Sierpe Viejo and Central American Spider Monkeys on all canals. Four


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rare species were also seen; 1 West Indian Manatee on California, 1 Lesser Scaup on Central, 1 Black-collared Hawk on Sierpe Viejo and 2 Muscovy Ducks (1 on Sierpe Viejo and 1 on California). These are all very positive results for the national park. A full list of all incidental species recorded can be found in appendix H.

Canal usage data for phase 114 recorded a total of 7 boats on the canals over the 26 survey days consisting of 2 taxi boats, 2 fishing boats, 1 tour boat and 2 boats of unknown activity. 5 of these 7 boats were recorded on Cao Negro, this canal being a main transit route for local and tourist traffic to access Tortuguero National Park.


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3.Jaguar Camera Trapping Project3.1 Introduction

The Jaguar is the third largest cat in the world and the largest in all of North and South America (Silver, 2004). Its range used to span from the South-western United States of America to Northern Argentina (Seymour, 1989). However, the current known, occupied range is about 54% of what it was in 1900 (Sanderson et al., 2002), ranging from northern Mexico to northern Argentina and are considered threatened across much of this range (Aranda 2000, Sanderson et al., 2002).

Although there has been much research done on turtles in the area, little is known about the population of Jaguars in TNP. The Tortuguero Conservation Area covers a total area of 180,925 hectares of which Tortuguero National Park covers a total area of 80,574 hectares, including marine territory (Bermudez, Plan de Manejo, 2004). The National Park guards have seen Jaguars on numerous occasions and have estimated that there are at least five individuals currently using the beach (Eduardo Chamorro comm. pers. 2008). GVI has initiated the use of cameras to estimate the population size of Jaguars in the parks coastal habitat.

Cameras have been used by the Sea Turtle Conservancy in the past with successful results. A camera trap left with a freshly killed turtle recorded 58 minutes of video of a male Jaguar feeding on a turtle (Harrison et al. 2005). We will adopt similar methodology and undertake field trials.

3.2

Aim

The aim of this project is to use camera trapping as a means of estimating the abundance of Jaguars using the coastal habitat inside TNP and to increase ecological awareness.


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The objectives are: 1. to determine the areas where Jaguars are present 2. to record their hours of activity and other habits 3. to compare Jaguar activity at different sites along the beach 4. to identify individual Jaguars by their rosette pattern 3.3 Methodology

The methodology for this project has received some slight modification from the previous one used; this can be found in Report 104. It was decided to experiment using scent stations in front of the cameras. Jaguars appear to walk at a fair pace when on the trails, the Bushnell Trophy Cam 2010 and 2011 do not have a fast enough trigger to catch a photo of the jaguar without the picture being blurry. This caused many of the jaguar pictures to be unidentifiable. What we needed was something that would make the jaguar stop in front of the cameras, so as to get a clean picture and make it possible for us to identify it. After talking to a jaguar biologist (Roberto Salom-Perez), who works with Panthera on jaguar camera trapping projects in Costa Rica, we decided to follow his suggestion of using Calvin Klein Obsession on our scent stations. This is sprayed every other week on the scent stations. We hope this will bring successful results to the camera trapping projects. A full methodology for scent stations can be found in Appendix C.

3.4

Results

A total of 106 camera nights during this phase allowed us to collect 91 Jaguar pictures and 93 pictures of other species. The pictures collected allowed us to identify 4 of our resident jaguars and two new juvenile jaguars currently active on the beach, both captured separately at our camera station at Mile 15. Following a suggestion by R. Salom-Perez and an article by Carrillo E. (2004) we decided to start experimentally using scent stations in some of our study sites. Scent stations were sprayed every other week with Calvin Klein Obsession. Phase 114 also allowed us to confirm the strong presence of one of our resident jaguars, Luca. He was captured on 5 different nights across 3 sites, ranging through most of the beach and the forest. Table 3-1 shows jaguar captures and recaptures between the 1st of October and the 9th of December 2011.


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We were also interested in understanding what the activity patterns were for these jaguars; camera traps take the date and time for every other picture they take. From the pictures collected of jaguars we can get an initial understanding of when and where these jaguars are active and some idea of their preferences. Activity and usage of the trails seems to starts between 18:00 and 20:00, with some peaks of activity around 00:00. Jaguars tend to then be active again between 01:00 to 05:00, probably returning from the beach after their patrols. Figure 3-1 illustrates the time of activity for jaguars captured during Phase 114. All pictures were used for this graph, even pictures of unidentified jaguars.

During this phase, we have also had a prolific number of other species of interest captured at night and daylight in our camera traps. We were lucky to capture shots of the elusive ocelot using some of the same trails used by the jaguars. This data also allows us to get a better understanding of prey species available for the jaguars during the winter. Here is a list of all the species captured in phase 114. Jaguar (Panthera onca) Central American Agouti (Dasyprocta punctata) Red Brocket Deer (Mazama Americana) Ocelot (Leopardus pardalis) Nine Banded Armadillo (Dasypus novemcinctus) Paca (Agouti paca) Common Opossum (Didelphis marsupialis) Great Currassow (Crax rubra) Great Tinamou (Tinamous major) Common Black Hawk (Buteogallus anthracinus) Unidentified Pigeon Species


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Figure 3-1 This bar chart illustrates the times at which all individual captures were taken during Phase 114. Identified and non-identified jaguars were included in this graph

Table 3-1 Jaguar Capture and RecapturesPhase 114 114 114 114 114 114 114 114 114 114 114 114 114 114 114 114 Jaguar Luca Name Alex Luca Luca Luca Molly Lyra Alex Pepito Molly Luca Alex Alex Luca Ricardo Ricardo First Capture Location Mile 17 Mile 15 Mile 15 Mile 17 South Boundary Mile 15 Mile 15 Mile 15 Mile 15 South Boundary Mile 15 Mile 15 Mile 15 Mile 15 Mile 15 Mile 15 Recapture N 6 4 7 8 9 5 2 5 1 6 10 6 7 11 1 2o

Yes

Yes

Date of recapture 25.10.2011 30.10.2011 30.10.2011 01.11.2011 01.11.2011 06.11.2011 10.11.2011 12.11.2011 17.11.2011 24.11.2011 25.11.2011 27.11.2011 28.11.2011 28.11.2011 19.11.2011 01.12.2011


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3.5

Discussion

Phase 114 was successful,following new techniques and methods, such as the use of scent stations and new capture sites we had an increased number of jaguars captured across the survey sites. This confirms the viability, and possible increase, of this healthy population. A table has been created to keep track of the jaguars active in TNP that we have been able to capture on our cameras. This table can then be updated at the end of every phase (Table 3-1). An archive of their rosette patterns allows us to identify all the individual jaguars. This spreadsheet is updated with site locations and GPS coordinates as well as any relevant comments. The use of scent stations proved to be helpful and allowed us to capture clearer images and videos of jaguars that stopped to sniff.

There is a strong possibility that Tortuguero National Park is becoming an important hub for a healthy population of Jaguars. Having an abundant and easy prey item, such as the nesting green turtles, is definitely a strong attractant for these jaguars that might be travelling long distances to reach the beach hunting ground. This survey allows us to keep a record of this population, its dynamics and behaviours. We are interested in their hunting and feeding patterns in the summer, during green turtle nesting season, and their activity in the winter months when the green turtles are not present. We are interested in understanding whether there is the possibility that many jaguars are migrating to Tortuguero in the summer months and then returning to other feeding grounds in the winter. We hypothesise that prey availability in the winter in TNP would not allow the viability of a large jaguar population with overlapping ranges such as the one that we have. Data from this phase showed that many of the jaguars actively feeding during the nesting season were still present in these first winter months. We hypothesize that Luca and Alex are the alpha males, we are still unsure about the nature of their relationship and we hope that analysis of the scats collected on the beach might tell us more. We also captured two new juvenile jaguars active in our survey area. There still seems to be new recruitment? Not sure if this word makes sense to me in the area even though nesting season is over. Most of the jaguars seem to be active between dusk and dawn.

For the next phases we are looking into expanding our camera trapping surveys down the beach line to mile 12. This way we would encompass all turtle hunting grounds used by GVI - Jalova, Parque Nacional Tortuguero, October - December 2011 Page 21

the jaguars in the TNP. We will keep using lures and scents, as allowed by permits, such as Calvin Klein Obsession, that have been proven successful on other jaguar camera trapping surveys in Costa Rica (Carillo et al. 2007). This will allow us to keep obtaining clearer and more consistent data as we will avoid blurry and unidentifiable pictures. We have been in contact with researchers from PANTHERA working in Costa Rica who are very interested in our project and impressed with the results we have been obtaining. We are currently working on permits through Panthera that will allow us to collect scat and hair samples from TNP to assist in the ongoing research efforts to genetically map (DNA microsatelliting) the Costa Rican jaguar population and obtain clearer data on the geographic provenience of jaguars currently in the TNP. This data could in the future allow us, and other researchers, to understand the spatial and range patterns of these jaguars and reinforce the creation and conservation of biological corridors to link populations in such a fragmented landscape.


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4.Jaguar Predation of Marine Turtles4.1 Introduction

Tortuguero National Park (TNP) is the most important nesting ground in the western hemisphere for Green Turtles (Chelonia mydas). In addition to the C. mydas there are also a significant number of Leatherbacks (Dermochelys coriacea) and the occasional Hawksbill (Eretmochelys imbricata) and Loggerhead (Caretta caretta) (Trong 2000). The nesting turtle population has been monitored on the parks beach since the 1950s and continues to be monitored today by the Sea Turtle Conservancy (STC).

Information on Jaguars (Panthera onca) predating on marine turtle is sparse. In TNP and many other areas, marine turtle predation by Jaguars has been recorded sporadically. 82 C. mydas were identified as being predated by Jaguars in Suriname from 1963-1973. On the same beach in 1980 one Jaguar killed 13 turtles within only a few days (Autar, 1994). On the Pacific coast of Costa Rica Jaguars have been recorded preying upon Olive Ridley Turtles (Lepidochelys olivacea), Black Turtles (Chelonia agassizii), and E. imbricata. Although, there has been much research done on turtles in TNP, from 1956 to 1995 there were only two C. mydas recorded to be killed by a Jaguar, one in 1981 and another in 1984 (Carrillo et al. 1994). Weekly walks on the beach to record the number of dead turtles killed by Jaguars began in 1997 as part of the STC turtle monitoring programme. The STC found four dead C. mydas killed by Jaguars in 1997, 25 in 1998, 22 in 1999, and two Leatherbacks in 1999 (Trong 2000). This predation upon turtles by Jaguars is not a new phenomenon but seems to have been increasing in the past 10 years within TNP (Trong 2000; Magally Castro, pers. comm.)

Due to a lack of human resources the Costa Rican Ministry of Environment and Energy (MINAE) invited GVI to continue data collection on Jaguar presence and predation of marine turtles in TNP. Data collection has now been conducted by GVI since 11th July 2005. Together with the data previously collected by MINAE, a more comprehensive understanding of Jaguar impact on the turtle population of TNP can be developed.


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4.2

Aim

The Jaguar project aims to document the presence of Jaguar on the beach of Tortuguero National Park and their predation of nesting marine turtles. 4.3 Methodology

The methodology for this project is explained in detail in report 082 and can also be found in Appendix D. The methodology used has remained unchanged since its last complete mention. 4.4 Results

During phase 114 we were able to carry out a total of 9 surveys of the beach, covering the 15 miles between Jalova and Tortuguero. The first survey had to take into account turtles that had been predated during interphase.This explains why the first survey had a disproportionately higher number of kills in relation to later surveys. This phase saw the end of the Green Turtle nesting season, with last peaks of activity around September, declining numbers into October with no more signs of nesting from mid November. The data was didvided into kills per week (calculated from the days since kill) so as to remove this bias from the data. A total of 49 Green Turtles (Chelonias mydas) were predated upon during the 9 weeks of surveying.

A total of 38 Green Turtle Nests were counted in total across the beach on all surveys. As shown in Figure 4-2. All these nests were counted across the first 5 surveys. No more tracks were recorded after the 9th of November 2011. An unusual find was a Leatherback nest on the 2nd of November 2011 at mile 10.5 of the beach, almost 4 months after the end of their nesting season. The line graph in Figure 4-1 illustrates the spread of the data over the 15 miles of the survey. Readers should keep in mind that Green Turtle tracks and Jaguar tracks are only noted if they are less than 24 hours old. The predated turtles on the other hand are recorded from the whole week between surveys. It was decided not to use data from one night to estimate for the whole week as the presence of Jaguars on the beach and the number of nesting Green Turtles are highly variable and can not be predicted or estimated.


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Figure 4-1 Spatial Distribution of Jaguar Presence, Predated Turtles and Turtle Nests

As illustrated by Figure 4-1 and 4-2, the data has a very variable spread across time and the survey area. There was a peak of predatory activity around mile 10 where about 30% of all this phases predated turtles were found. This is probably due to the presence of one or more jaguars using the same location as a hunting ground for a long period of time. Jaguar presence was fairly constatnt across the 9 weeks of surveying; one of the surveys data for tracks was not taken into account due to heavy rains which cancelled any signs of tracks on the beach. Fresh signs of jaguar presence form the previous night were always ( do thet mean always or only?)found between Mile 11 and Mile 15 of the beach.


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Figure 4-2 Number of Green tracks, predated turtles and jaguar presence for the 9 surveys

Figure 4-3 This boxplot shows the different spread of data between jaguar presence close to human presence (1) and further from human presence (2).


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We were interested in knowing if human presence was having an effect on jaguar roaming activity Decreased activity seemed to coincide with distance from human settlements.. To test this the 15 miles of the beach were divided into two data sets, 3.5 miles on each side of the survey area (up to mile 14.5 from Jalova and up to mile 7 from Tortuguero) were included in the higher human impact data set whilst the middle section of the survey area (7.5 miles) was included in the lower human impact data set. Data was normally distributed. A significant difference was found between the two data sets (p= 0.033)

supporting the hypothesis that human presence does have a significant impact on the jaguars hunting and spatial patterns. The Boxplot in Figure 4-3 summarise the descriptive statistics of this data set and illustrate the differences.

An increase in Jaguar range and activity on the beach coincided with the end of the nesting season. To test this we divided the JaguarPresence data into Nesting season and Post-Nesting season sets. This allowed us to test if there was a significant increase in activity and if Jaguars were less affected by human presence during the winter months. Data sets were normally distributed. Data sets were tested using a paired samples t-test and were found to be different (p=0.043). Jaguars also appear to have increased their activity on the beach once the nesting season came to an end. An ANOVA was used to test whether there was any difference between Jaguar activity with distance to human settlements in non nesting season. There was no significant difference (p=0.052)on this occasion.

4.5

Discussion

We have reason to believe that the nesting beach at Tortuguero National Park is becoming an important hub for a healthy Jaguar population. Predation on Green Turtles has been increasing in the past two decades (Troeng, 2000; Verissimo, 2011). However the impact of Jaguars on the nesting population can still be considered negligible given the number of nesting turtles per season. What is happening is an important and delicate interaction between two flagship species that are well known and appreciated by the general public. Understanding this interaction is essential for a constructive management plan to be built. This phase coincided with the end of nesting season, number of nesting turtles plummeted and no nests were recorded after the 9th of November. Jaguar activity was still very high GVI - Jalova, Parque Nacional Tortuguero, October - December 2011 Page 27

and constant across the beach. Camera traps set on the beach have given us the opportunity to individually identify 9 Jaguars actively hunting between mile 18 and 15 of the beach (GVI, Camera trapping survey, 2011). This allows us to confirm the constant presence of jaguars on the beach of Tortuguero National Park. Jaguars patrol the beach in search of prey every night in Tortuguero National Park during the Green Turtle nesting season. Jaguars seem to patrol the beach without following a specific pattern during turtle nesting season. Jaguars will follow turtle tracks in the sand up and down, and then will continue moving if they do not find the turtle at either end of the track. During the winter season the Jaguars keep patrolling the beaches on their own and sometimes in pairs. Jaguar activity during later surveys, when nesting season was over, appeared higher. Jaguar tracks will sometimes follow the vegetation line, the quad bike tracks at the centre of the beach or the high tide line. Jaguars are opportunistic feeders and will change their activity patterns in accordance to their major prey species (Rabinowitz & Nottingham, 1986). Carrillo et al. (2009) found that Jaguars changed their movement and hunting patterns in accordance to availability of marine turtles in Corcovado National Park. The Jaguars might also be using the beach during the winter months for other purposes: such as encountering new mates, exploring and expanding their ranges. We have recorded many signs of social encounters between Jaguars during our surveys. Examples of this are: scuffles, playful activity and signs of mating across the beach.

Our track surveys show us that Jaguar presence throughout the beach peaks between mile 8 to 11 and mile 12 to 15. The highest activity appears to be confined to areas that are the furthest away from human presence. We found that jaguars had higher levels of activity the further they were from the Jalova GVI base station to the South and Tortuguero town to the North. Although Jaguars in Tortuguero National Park are particularly habituated to human presence they still prefer to hunt and patrol areas of the beach where they have less of a chance of encountering people. Activity increased after the end of nesting season and Jaguars increased their ranges to areas closer to human settlements, both on the Jalova South end and the Tortuguero North end. This is probably due to the fact that the STC and GVI Turtle Patrols, as well as tourist groups and poachers, stopped


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being active at night on the beach thus leaving the beach free for the Jaguars alone. This allowed them to increase their ranges and their patrol areas of the beach, in search of mates, food and possibly waiting for the first turtles of the new turtle season.

It is of great importance that this incredible interaction between two flagship species is continuously observed and analysed to understand if a right balance can be found. The Jaguar population in the TNP seems to be increasing, leading to a larger strain on the turtle nesting grounds that are already taking a toll from illegal human poaching. Jaguars on the other hand are facing large amounts of habitat loss, fragmentation and a decrease in prey numbers. Having found this high protein, abundant and easy to catch meal that just comes back year after year why should they go anywhere else? The increase in the resident population may reach a non-viable limit forcing healthy Jaguars out to repopulate the Caribbean slopes of Costa Rica. Continuous management and research is needed to better understand this interaction and its possible repercussions, both positive and negative for both species.


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5.Incidental Species Study5.1 Introduction

The Incidental Species Study is an ongoing recording of animal species found in and around the Jalova Biological Station, occupied by Global Vision International, Costa Rica. Data is collected on a casual basis each day, rather than as part of an organized survey. Currently, the study only records mammals, birds, amphibians and reptiles as these groups have excellent publications to enable identification of them. It is currently impossible to identify invertebrates to a species level with the resources that GVI possesses, but taking photos of any species seen is to be encouraged particularly with butterflies and moths, so that a photo library can be maintained with the possible long-term goal of identifying them all.

5.2

Aim

The Incidentals Species Study aims to build a large species database of the amphibians, birds, mammals and reptiles present in the Jalova area of Tortuguero National Park. Based on frequency of sightings this database will indicate estimates in species abundance between and across (i) zones and (ii) class, illustrate species which demonstrate habitat preferences and identify seasonal trends, particularly with migratory species. Additional to this, forest health can also be assessed by documenting sightings of indicator species such as Central American Spider Monkey (Ateles geoffroyi) and Whitelipped Peccary (Tayassu pecari). Future aims for the Incidentals Species Study include collecting data on specific species behaviours as well as breeding and nesting habits to further our knowledge on the animals inhabiting Tortuguero National Park.

5.3

Methodology

The methodology for this project is to explain in detail in report 111 and can also be found in Appendix F.


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5.4

Results

During phase 114, there was an average of 31 sightings per day and this resulted in a total of 255 species being recorded. Of these 255 species, 13 were new species for 2011 (i.e. had not been recorded during any of the other phases of 2011). These species new to 2011 and the dates that they were seen, are shown in table 5-1.

Table 5-1 Species recorded for the first time in 2011

Class

Common Name

Scientific Name

Date Recorded

Aves

Belted Kingfisher Crimson-fronted Parakeet Lesser Yellowlegs Ruddy Turnstone Swainsons Thrush Bay-breasted Warbler Cinnamon Becard Gray Catbird Mangrove Swallow

Ceryle alcyon Aratinga finschi Tringa flavipes Arenaria inetrpres Catharus ustulatus Dendroica castanea Pachyramphus cinnamomeus Dumetella carolinensis Tachycineta albilenea

06/10/2011 06/10/2011 06/10/2011 06/10/2011 13/10/2011 04/11/2011 18/11/2011 28/11/2011 28/11/2011

Mammalia

West Indian Manatee Kinkajou

Trichechus manatus Potos Flavus

06/10/2011 03/11/2011

Reptilia

Common Blunthead Carpenters Anole

Imantodes cenchoa Norops carpenteri

17/10/2011 20/10/2011


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Table 5-2 Total number of species recorded per zone.

Zone A B C D E F

Total number of species recorded 903 170 481 112 157 92

Figure 5-1 Total percent of species recorded per zone

Figure 5-1 illustrates the total percent of species recorded per zone. Zone A demonstrates the highest percent of 68.72% of species recorded. Zone C shows 36.6% of recordings, whilst zones B, E, D and F demonstrate the lowest species recorded with 12.93%, 11.94%, 8.52 and 7% respectively.


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Table 5-3 Total number of dates recorded per zone from a maximum of 70 days

Zone A B C D E F

Number of dates 62 49 62 38 41 48

Figure 5-2 Distribution of records per class across zones

The distribution of species recorded per class across all zones is illustrated in figure 5-2. The majority of recordings belong to Aves (76.18%). Reptilia have a record of 17.07%, whilst Mammalia and Amphibia have 4.07% and 2.66% respectively.


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Figure 5-3 Distribution of Amphibia records per zone

The distribution of Amphibia recorded per zone is illustrated in figure 5-3. Zone A and D showed the highest percentage of Amphibia recorded with 4.42% and 4.46 respectively. Zone E had 1.91% of records and zone C had just 0.62% of records. Zones B and F had 0% of Amphibia recorded within them. (No recordings were expected for zone F as Aves can only be recorded here).

The distribution of Aves recorded per zone are illustrated in figure 5-4, evidently zone F showed the highest percentage of recordings with 100%, as no other class can be recorded in this zone. Zone E had a recording of 89.8%. Zones A (73.64%), B (87.64%) and C (80.66) showed a high percentage of recordings. Zone D presented the lowest recordings of 21.42%.


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Figure 5-4 Distribution of Aves records per zone

Figure 5-5 Distribution of Mammalia records per zone


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Figure 5-6 Distribution of Reptilia records per zone

Figure 5-5 illustrates the total distribution of Mammalia records per zone. Zone D shows the highest percentage of recordings at 39.28%. Zone B showed 8.23% whilst the remaining zones show a percentage of less than 3%, these are as follows, zone A 0.55%, zone C 2.91%, zone E 0.63%/ (No recordings were expected for zone F as Aves can only be recorded here).

Figure 5-6 illustrates the distribution of Reptilia recorded per zone. Zone D showed a higher percentage than zone A with 34.82% and 21.37% respectively. The following percentages per zone are as follows, zone B 4.11%, zone C 15.8%, zone E 7.64% and zone F 0%. (No recordings were expected for zone F as Aves can only be recorded here).

Statistical Analysis Species within zone ANOVA: two factor without replication demonstrated no significant difference (P > 0.05) between the total number of species recorded across zones, P 3.42E-16. The ANOVA: two factor without replication for total number of species recorded between zones GVI - Jalova, Parque Nacional Tortuguero, October - December 2011 Page 36

demonstrated 10 positively significant relationships (i.e. P < 0.05) out of the possible 15 comparisons (table 4). Zone A showed a strong significant difference between all other zones (table 5-4). Zone B also demonstrated a strong significant difference with zone C and a significant difference were also seen between zone B and F (P < 0.05) (table 5-4). Zone C too demonstrated a strong significant difference between all other zones (P < 0.05) (table 4).

Species within class ANOVA: two factor without replication demonstrated no significant difference (P > 0.05) between the total number of species recorded, from all zones, across class, P 4.17E-11 (table 5-5). The ANOVA: two factor without replication for total number of species recorded, from all zones, between classes demonstrated five positively significant

relationships (i.e. P < 0.05) out of the possible six comparisons (table 5-5). A strong significant difference was seen when comparing the total number of recordings for Aves with both Amphibia and Mammalia. Reptilia also demonstrated a strong significant difference between all other classes (table5-5).

Table 5-4 Comparison of total number of species recorded per zone. X denotes no significance between zones. P denotes P-value after analysis Zones A B C D E F

A B P 3.31E-05 < 0.01 C P 0.000554 < 0.01 D P 0.000124 < 0.01 E P 7.1E-05 < 0.01 F P 3.89E-05 < 0.01 P 0.019186 < 0.01 x P 2.52E-05 < 0.01 x P 9.63E-05 < 0.01 P 0.000115 < 0.01 P 1.56E-05 < 0.01 x x x


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Table 5-5 Comparison of total number of species recorded per class. X denotes no significance between class. P denotes P-value after analysis Class Amphibia Amphibia Aves Mammalia Reptilia

Aves

P 2.4E-05 < 0.01

Mammalia

x

P 7.82E-05 < 0.01

Reptilia

P 0.000131 < 0.01

P 7.69E-05 < 0.01

P 0.00743 < 0.01

A list of species from phase 114 can be found in Appendix A. Included within is a comparison of the zones each species was recorded and the percentage of days seen from phase 114 in comparison to phase 104.

5.5

Discussion

New species recorded by class per zone Phase 114 comprised 70 days and within these days a total of 13 new species were sighted for the year 2011 (table 1). This is almost 1% of the 255 total of number of species recorded this phase.

Aves

Zone A The widespread and very common passage migrant, Catharus ustulatus, was an interesting sighting as it was recorded outside of its usual season. This primarily migrant thrush is common from late September to mid-November but it was witnessed in TNP in mid-October (13th &17th).


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Dendroica castanea is a common passage migrant bird from mid-September to midNovember on the Caribbean slope. This bird found commonly on lowlands was observed twice between the beginning to mid-November (4th & 29th) on overcast days.

The common Pachyramphus cinnamomeus was recorded three times in the month of November (18th, 21st & 24th) on overcast days. It is commonly sighted in gardens and forest edges on the Caribbean coast.

The common winter resident Dumetella carolinensis is the only gray bird in Costa Rica that has a black cap and a rufous vent. It was observed on two consecutive days in November. This bird was observed feeding around the compost recycling containers in zone A. It is usually a difficult bird to see as it prefers to forage in tangled second growth and forest edges (Garrigues et al 2007).

Zone C Dumetella carolinensis was witnessed in the area surrounding zone A, it was recorded in zone A on the previous day (see zone A for details).

Zone E The common Ceryle alcyon was observed twice within the month of October (6th & 10th). This species of kingfisher is used in the canal bird survey study. It is a non-migrant bird found along both coasts of Costa Rica.

Aratinga finschi is endemic from south-eastern Nicaragua to western Panama. Although it is common on the Caribbean slope it has only been recorded once during 2011. This may be due to the difficulty in the correct identification of parakeets. This species inhabits forest edges and although this parakeet was found in zone E this zone is surrounded by forest.

The North American migrant sandpiper, Tringa flavipes, can be seen from August to May. It wades in a variety of wetland habitats such as river banks and puddles. Does specify any recorded sighting?


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The recording of Arenaria interpres is interesting as it is a North American migrant bird that is uncommon on the Caribbean coast however common the Pacific coast. It was found foraging on mud and sand exposed by the sea at the river mouth on October 6th.

Tachycineta albilenea was observed at the river mouth skimming the water surface. Swallows are often seen doing this behaviour however identifications can be tough as the birds move with great speed.

Mammalia

Zone C One of the most frequently seen nocturnal mammals of Costa Rica is the Potos flavus. It was seen twice in the month of November (3rd & 13th). Their presence is a sign of a healthy forest as they cannot survive in deforested areas (Wainwright 2007). They are believed to be good seed dispersers for many plants as they seldom spend long in a single feeding tree. This arboreal species was seen taking refuge in a coconut tree during the hours of darkness.

Zone E Central Americas only herbivorous aquatic mammal, Trichechus manatus, was seen surfacing briefly near the river mouth at Jalova. Sightings of T. manatus in Costa Rica are very rare for a number of reasons. They are a rare species which live in murky waters and are most active at twilight and at night. This way of life may be primarily due to increased human pressures. Their low metabolic rates allow them to remain submerged for periods of up to 20 minutes when resting and emerge briefly every five minutes when active (Wainwright 2007), thus resulting in low sightings of this aquatic mammal.

Reptilia

Zone A Imantodes cenchoa is a docile common species of snake active primarily at night and can be found in both primary and secondary forest. It was found twice in the month of October


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(17th & 19th) in the low vegetation surrounding zone A and once in November (4th) on the porch of the staff house.

Zone D The uncommon Norops carpenteri was found in its preferred forested habitat. This unique species of anole was first described in 1971 by Echelle et al (Guyer et al 2005). N. Carpenteri is very cryptic in coloration and appears to favour lichen-covered-exposed surfaces, this may explain why this species of anole had not been recorded before October 20th for 2011.

Total number of species recorded per zone This study shows that the zones with the greatest number of species recordings were zones A and C. Zones B and E showed a similar result, whilst zones D and F also demonstrated similar results (table 2).

Zone A Zone A had the overall highest number and percentage of species recorded (table 2, figure 1). This zone resulted in sightings 62 out of the 70 days of phase 114 (table 3). The number of sightings within this zone is relatively high as GVI staff and volunteers have a constant presence. This zone alsodemonstrated a strong significant difference in the total number of species recorded between it and all other zones (table 2). Within each of their classes Aves demonstrated the highest total percentage of records, 73.64%, Reptilia saw 21.37%, Amphibia 4.42% and Mammalia 0.55% (figures 3 6). Within zone A, Aves are easily viewed and thus may be the result for this classs high percentage, whilst the rare sightings of Mammalia may be as a result of the constant human presence throughout this zone. Phase 114 occurred during the rainy season, thus one would expectthe percentage of Amphibia would be greater than 4.42%. This low percentage of records may not be a true representation to the great numbers of Amphibia found within zone A; this may be due to the severity of the heavy rains which hindered our movement throughout the zone.


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Zone B Zone B was used on a daily basis with 49 out of the total of 70 days (table 3, figure 1) resulting in recorded do you mean record?sightings. It is a very unique habitat and thus may too result in low species diversity. This zone demonstrates the second highest percentage of Mammalia records (8.23%) across all zones (the greatest percentage of recordings is zone D, 39.28%). The recordings within zone B range from sightings of white-throated capuchins (Cebus capucinus), Hoffmanns two-toed sloth (Choloepus hoffmanni) and central American spider monkey (Ateles geoffroyi) at the small edge of forest surrounding the beach, jaguar (Panthera onca), white-nosed coati (Nasua narica), red brocket deer (Mazama americana) and common opossum (Didelphis marsupialis) on the beach to bottlenose dolphins (Tursiops truncates) swimming in the sea. The common opossum was found shortly after a jaguar attack. The common opossum was still alive and had six young attached to her underbelly. From the jaguar tracks it is thought that the jaguar was either scared away from her do you know its a her? prey or the adult jaguar was teaching the younger jaguar how to hunt. Within each of their classes Aves received the highest percentage of species recorded for this zone of 87.64% Reptilia saw 4.11% and Mammalia saw 8.23%% of recordings within zone B (figures 3 - 6).

Zone C The total number and percentage of species recorded within zone C (table 2, figure 1), demonstrated an equal number of sightings as zone A with 62 out of the 70 days of phase 114 resulted in species recordings (table 3). Zone C completely encircles zone A and too may be a reason for the high frequency of sightings. Within each of their classes, Aves had the highest total percentage of recordings for this zone 80.66%, Reptilia demonstrated 15.80%, Mammalia showed 2.91% and Amphibia saw 0.62% within zone C (figures 3 - 6). The landscape of zone C is considerably open with grasses kept low by grazing cattle. Thus it allows for easy viewing of birds and also accommodates prime basking sites for reptiles.

Zone D Within each of their classes, both Mammalia and Reptilia were found to have a similar high percentage of records, 39.28% and 34.82%, respectively. Aves demonstrated 21.42% of


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records and Amphibia 4.46% (figures 3 6). Zone D had the lowest number of sightings (table 3) over the total 70 days. Species were recorded just over half of the study period. This may be as a result of the heavy rainfall during phase 114. As species recorded for this study are primarily recorded whilst GVI staff and volunteers are going to and from BAS (Biodiversity Assessment Survey) sites and because severe flooding restricted the number of BAS, this had a negative effect on our ability to record species for this zone.

Zone E This zone is predominantly used in the early mornings (5-8am) whilst survey teams get the motor boat ready. The number and percentage of species recorded (table 2, figure 1) are encouraging as they show an increase from phase 113. Within each of their classes, Aves was found to have the highest percentage of species recorded 89.8%, Reptilia, Amphibia and Mammalia demonstrated a very low occurrence, 7.64%, 1.91% and 0.63%, respectively (figures 3 6). Due to zone E being water rich, it may be expected that many of the recordings for this site belong to Aves.

Zone F Zone F demonstrated an encouraging total number and percentage of species recorded (table 2, figure 1) with a total of 48 days out of the total 70 days of phase 114 (table 3) showing recordings. The purpose of zone F is to solely record bird species and thus explains the reasons for 100% of the total number of recordings belonged to Aves and none belonged to any of the remaining classes (figures 3 6) in the study.

Total number of species recorded per class This study shows that the two classes with the greatest number of recordings belonged to Aves and Reptilia (figure 2). A significant difference was observed when the total number of species recorded in both zone A and zone C were compared with all other zones (table 4). A significant difference (P < 0.01) was also observed when comparing the total number of species recorded in both Reptilia and Aves to all other classes (table 5).


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Future work The Incidentals Species study during phase 114 demonstrated some very interesting results, in particular with the addition of 13 new species for the year 2011. An increase in the quantity of incidental walks, both diurnal and nocturnal, will aid in the ongoing analysis of species frequency, habitat preferences and ecosystem health throughout the Jalova area.


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6.Biodiversity Assessment Project6.1 Introduction

The Biodiversity Assessment Survey is a survey that was based upon the Incidentals Species Study. It is a more structured survey that notes recordings of animal species found in and around the Jalova Biological Station, occupied by Global Vision International, Costa Rica. Data is collected almost every day by scheduled surveys that take part on four trails.

Currently, the study only records mammals, birds, amphibians and reptiles as these groups have excellent publications to enable identification of them. It is currently impossible to identify invertebrates to a species level with the resources that GVI possesses, but taking photos of any species seen is to be encouraged particularly with butterflies and moths, so that a photo library can be maintained with the possible long-term goal of identifying them all.

6.2

Aim

To collect more information about the abundance, behaviour and local distribution of mammal, bird, reptile and amphibian species. The numbers gathered on the number of sightings will be compared against the different trails on a yearly basis as well as by phases, which run every ten weeks. Potential aims are to start collecting data on species abundance by counting individuals seen, and also to collect information on breeding success by recording breeding behaviour or sightings of young.

6.3

Methodology.

The methodology for the project remains constant with the previous report, where the methodology is mentioned in full. For methodology details see Appendix G.


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6.4

Results

A total of 86 surveys have been completed throughout the course of phase 114, these surveys collected 1335 individual seen records and 157 heard records, comprising of 169 species (Appendix H). In addition the surveys collected 24 individual mammal track records, comprising of 7 species (Appendix H). A per-transect break down of the species and record data can be observed in table 6-1.

Number of species and records between transects Statistical analysis shows that no significant differences occur in the number of species recorded (P-value = 1.08E-17, >0.05) or the number of individual records recorded (Pvalue = 1.43E-18, >0.05) on each transect. Although no overall significance was found between transects figure 6-1 illustrates that some transects did record less species and records than others.

Number of species recorded by class Of the 174 species recorded throughout the phase 119 were birds, 26 were reptiles, 16 were mammals and 13 were amphibians, therefore as can be seen in figure 6-2 Aves were the most commonly recorded species. The breakdown of species by class per transect can be observed in table 6-2.


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Table 6-1: Number of Surveys, Species, Seen, Heard and Track Records per TransectTransect North Trail 17-16 Number of Surveys Number of seen species Number of Records Number of heard species Number of Records Number of track species Number of Records 13 North Trail 16-15 13 8 14 North Boundary South Trail

50

23

21

81

247

321

44

336

14

8

5

11

37

17

10

22

0

0

2

2

0

0

2

5

Transect

Coconut Plantation

South Boundary 9

Juana Lopez

Kingfisher Trail

Overall

Number of Surveys Number of seen species Number of Records Number of heard species Number of Records Number of track species Number of Records

13

7

9

86

56

22

23

45

161

207

42

45

93

1335

6

11

3

6

27

22

22

9

17

157

0

1

4

2

7

0

1

8

8

24


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Figure 6-1 Average number of species and records per transect

Figure 6-2 Total number of species recorded by class


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Table 6-2: Number of Species by Class, Seen and Track Records per TransectTrail Class Amphibia North Trail 17-16 Aves Mammalia Reptilia Amphibia North Trail 16-15 Aves Mammalia Reptilia Amphibia North Boundary Aves Mammalia Reptilia Amphibia South Trail Aves Mammalia Reptilia Amphibia Coconut Plantation Aves Mammalia Reptilia Amphibia South Boundary Aves Mammalia Reptilia Amphibia Juana Lopez Aves Mammalia Reptilia Amphibia Kingfisher Trail Aves Mammalia Reptilia Amphibia Overall Aves Mammalia Reptilia Seen Species 1 25 7 17 3 22 5 13 0 10 3 8 1 64 3 12 0 46 3 7 3 7 4 8 3 6 3 11 4 27 3 11 10 114 11 26 Records 1 50 84 112 3 47 61 210 0 44 13 19 17 194 24 101 0 182 9 16 7 9 7 19 3 6 6 30 6 50 12 25 37 550 216 532 Heard Species 2 11 1 0 1 6 1 0 0 3 2 0 2 7 2 0 1 5 0 0 2 9 1 0 0 2 1 0 0 5 1 0 3 22 2 0 Records 7 23 7 0 4 7 6 0 0 10 4 0 2 13 8 0 2 20 0 0 3 14 5 0 0 6 3 0 0 10 7 0 18 99 40 0 Tracks Species N/A N/A 0 N/A N/A N/A 0 N/A N/A N/A 2 N/A N/A N/A 2 N/A N/A N/A 0 N/A N/A N/A 1 N/A N/A N/A 4 N/A N/A N/A 2 N/A N/A N/A 7 N/A Records N/A N/A 0 N/A N/A N/A 0 N/A N/A N/A 2 N/A N/A N/A 5 N/A N/A N/A 0 N/A N/A N/A 1 N/A N/A N/A 8 N/A N/A N/A 8 N/A N/A N/A 24 N/A


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Number of Records by Class The number of records by class was found to be significant (P-value =0.037318, 0.05), Mammalia (P-value = 1.58E-10, >0.05) and Reptilia (Pvalue = 1.25E-17, >0.05) showed no significance when compared across transects (figure 6-7). Amphibia records (P-value = 0.033833,

gvi jalova expedition phase report october-december 2011 114

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