ben friedel 2014 nss presentation
TRANSCRIPT
![Page 1: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/1.jpg)
Multiple Mark and Recapture Population Size Estimates of Stygobromus tenuis potomacus in a
Hypotelminorheic Habitat
Benjamin D. Friedel, Jonathan Williams and Dr. Daniel W. Fong
American University
![Page 2: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/2.jpg)
Hypotelminorheic Habitats• Hypotelminorheic Habitats
- Aquifer fed by subsurface water- Underlain by clay - Surface window found on slopes at “seepage springs”
![Page 3: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/3.jpg)
Seepage Springs
• Seepage Spring– Diffuse percolation ofhypotelminorheicgroundwater – Key access point to organisms thatlive in hypotelminorheic environments Seep C
![Page 4: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/4.jpg)
Stygobromus tenuis potomacus• Freshwater amphipod crustacean• Common to hypotelminorheic aquatic habitats in
Washington, DC area (found in seepage springs)• Besides species and habitat descriptionlittle is knownabout their basicbiology
![Page 5: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/5.jpg)
Seepage Spring Sites• Two seepage springs (seeps B & C) studied
were 5 minutes from campus• Allowed for weekly sampling
Washington DC Metropolitan Area
![Page 6: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/6.jpg)
Seepage Spring Sites
• Sampled Seeps B and C only 5.8m apart
• Conducted multiple-mark multiple-recapture estimates of Stygobromus population size at both seepage springs – Data shown for weeks 1-16 (02/20/14 to
06/06/14)
![Page 7: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/7.jpg)
Methods
• Weekly sampling of Seeps B and C
• 2-3 people collected Stygobromus in a 1x2m area of the seepage spring for 15 minutes
• Stygobromus were counted in the lab– Total numbers, ovigerous females and recaptures
![Page 8: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/8.jpg)
Methods• Marked with neutral red stain– Stained animals in 100mg/L neutral red dye for
24-48 hours before the next week of sampling– After the next week’s collection, stained animals
were returned to original habitats
![Page 9: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/9.jpg)
Neutral Red Marking
• Marking with neutral red stains the cuticle and hepatopancreas
Hepa
topa
ncre
as
![Page 10: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/10.jpg)
Data Analysis Methods
• Schnabel (S) and Schumacher-Eschmeyer (S-E) methods were used to estimate population size (N)– Assumptions• closed population • lasting marks that do not affect capture ability,
behavior or survival
![Page 11: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/11.jpg)
Data Analysis Methods
Schnabel Schumacher-Eschmeyer
• s=#sample events• Ct= # captured at tth (16th) sample event• Mt= total # marked individuals in pop. During tth sample event• Rt= # recaptures collected during tth sample event
![Page 12: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/12.jpg)
Results• Raw Data Example Collected for Chain Bridge Seeps B and C
C= # animals collected that week
R= # of recaptures collected that week
M = Total # of animals marked and released at that week
![Page 13: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/13.jpg)
W1 W2 W3 W4 W5 W6 W7 W8 W9 W10 W11 W12 W13 W14 W15 W16-50
-40
-30
-20
-10
0
10
20
30
40
0 0 0 0 0 0 0 2 2 6 4 6 317 20
40
Collected and Recaptures 2014 C
Sampling Week
Indi
vidu
als
Colle
cted
W1 W2 W3 W4 W5 W6 W7 W8 W9 W10 W11 W12 W13 W14 W15W16-50
-40
-30
-20
-10
0
10
20
30
40
0 0 0 0 0 1 2 1 1 6 10 154 6
14 17
Collected and Recaptures 2014 B
Sampling Week
Indi
vidu
als
Colle
cted
Comparing Recaptures from Seeps C & B
![Page 14: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/14.jpg)
Population Estimates2014 CB Stygobromus Population Estimates• 2014 - 703 marked and
released, 177 recaptured Seepage Springs B and C combined
B-S B-SE C-S C-SE0
200
400
600
800
1000
1200
528448
1002820
Seep-Analysis Method
Popu
latio
n (In
divi
dual
s)
![Page 15: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/15.jpg)
Ovigerous Females
W1 W2 W3 W4 W5 W6 W7 W8 W9 W10 W11 W12 W13 W14 W15 W16-50
-40
-30
-20
-10
0
10
20
2 0 0 0 2 3 2 2 1 34
10
1 2 1 0
2014 B
Week
Indi
vidu
als C
olle
cted
W1 W2 W3 W4 W5 W6 W7 W8 W9W10
W11W12
W13W14
W15W16
-50
-40
-30
-20
-10
0
10
20
2
12
1 1
10 610
15
53
1114 12
20
9 8
2014 C
Week
Indi
vidu
als C
olle
cted
2014 Total OvigerousSeep B Seep C
33 1390.19 0.81
Total CollectedS B S C
299 4820.38 0.62
Total Ov/CS B S C
0.11 0.29
![Page 16: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/16.jpg)
Conclusions• Population dynamics discrepancies between Seeps
C and B – Population estimate for Seep C is greater than Seep B
– More ovigerous females (overall and proportion of captures) in Seep C than Seep B
Total Ovigerous/Total Collected
Seep B Seep C
0.11 0.29
![Page 17: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/17.jpg)
Conjectures
• Seeps B and C could be draining two separate hypotelminorheic systems
• Seeps B and C could be connected with an environmental preference by Stygobromus for one seep over the other
![Page 18: Ben Friedel 2014 NSS Presentation](https://reader036.vdocuments.mx/reader036/viewer/2022081505/587632db1a28ab68098b5125/html5/thumbnails/18.jpg)
Citations• Culver, D.C. The secret world of seeps (PowerPoint slides). Retrieved from
http://www.nps.gov/cue/events/seeps_dec2007/presentation_culver.pdf
• Drolet, D. & Barbeau, M.A. (2006). Immersion in neutral red solution as a mass-marking technique to study the movement of the amphipod Corophium Volutator. Journal of Crustacean Biology, 26(4): 540-542.
• Holsinger, J. (1967). Systematics, speciation and distribution of the subterranean amphipod genus Stygonectes (Gammaridae). Washington, DC: Smithsonian Institution Press.
• Krebs,C.J. (1999). Estimating abundance: Mark-recapture techniques. In: Ecological Methodology. 2nd ed. Menlo Park, CA: Benjamin/Cummings.
• Pipan, T., Fišer, C., Novak, T., & Culver, D.C. (2012). 50 years of the hypotelminorheic: What have we learned? Acta Carsologica, 41(2-3): 275-285