Efficacy of sampling techniques for surveying the community of
reptiles and amphibians in a pocosin wetland
Stan J. Hutchens*, Christopher S. DePerno, and Kenneth H. Pollock, North Carolina State University, Fisheries and Wildlife
Sciences Program, Box 7646, Raleigh, NC 27695
Table 1. Species composition based on capture data for all techniques,
Concern about reptile and amphibian population declines • During 2005-2006, 32 species were recorded in
has increased globally. These taxa occupy vital positions BNS. Numbers of species and individual captures
Taxon # Species # Individuals
in ecosystems and concern over population declines has varied between taxa (Table 1).
Salamanders 2 13
prompted new efforts to measure species richness.
• Capture numbers varied by sampling technique
However, inventory research frequently employs only two Lizards 3 13
or three different sampling techniques. Consequently, Turtles 9 98
certain species may be missed depending on the Snakes 10 153 • Subsequently, additional techniques added new,
techniques used and species behavior. Frogs/Toads 8 1308 “unique” species not previously recorded (Fig. 2).
Totals 32 1585
Three techniques contributed 1 additional species,
Objective whereas 1 technique captured 8 species not
To evaluate the efficacy of multiple sampling techniques sampled by another technique.
Number Individuals Captured
for surveying the reptile and amphibian community in a 1000 • Primary methods for reptile and amphibian sampling
pocosin wetland. 600
(i.e., drift fence arrays; VES; and coverboards)
captured many individuals of the most common
200 96 76
16 31 5 38 22 0 species (Figs. 1, 2).
S ys es s ts s s p
ys VE arr a rch ng g
tr a • Secondary sampling techniques (i.e., aquatic funnel
ea rd ea i ra y s oad ne fi s sk
nc oa ds pip et fun ay Ba
if t fe v erb R oa VC Li n ud it
tic Cr traps, line transects, and opportunistic capture)
P A nis
r tu Aq
po provided a more robust sample of species diversity.
•Also, secondary techniques:
Figure 1. Number of individuals captured by sampling techniques • Are less expensive
during May - August 2005-2006. VES = visual encounter survey.
• Require less effort
• Are reasonable alternatives for measures of
N u m b er S p ecies C ap tu red
20 16 • Opportunistic captures afforded a greater knowledge
15 10 11 10
8 7 8 of the reptile and amphibian community than any
1 1 3 11 3 2 2
5 0 0 00 standardized technique used.
Study Area/Methods 0
ys ES s s ids ts ys s s ps tr a
• For example, road cruises contributed 38% of the
y he gr ec se ap t ra
a a ar c i ng ns r ve r ui l tr sh i ng
ce rd se tr a su dc ne yfi sk
pip or y Ba
• The study was conducted at Bull Neck Swamp (BNS), a ift
fe n erb
C Li n
d it pr .
fu n C r a unique species sampled on BNS.
Dr C ov Op ua
24.3 km2 pocosin wetland in Washington County, NC Capture Technique • Future studies surveying reptile and amphibian
owned and managed by the Fisheries and Wildlife Sciences communities should incorporate as many techniques
Total Species Added Species
Program at North Carolina State University. as economically and spatially possible to determine
• All techniques were designed as simple or systematic Figure 2. Total and unique species captured by sampling techniques, species diversity.
May-August, 2005-2006. VES = visual encounter survey.
random distributions and implemented from May to August,
2005 and 2006.
*Contact Info: Stan Hutchens, email@example.com, (919) 513-7558.