| dc.description.abstract | Long-lived species such as turtles may appear to have healthy persistent
populations if adults are consistently observed; however, study of size structures can
reveal declining populations left vulnerable by limited juvenile recruitment. Longterm
studies can provide insight into community and population structure changes
as well as test the efficacy of previously implemented mitigation measures. Two
intensive turtle studies that included trapping occurred in Point Pelee National Park
(PPNP) prior to my work: Rivard and Smith (1973) and Browne (2003). Browne
(2003) studied the populations, capturing six species, and started the PPNP nest
protection program to mitigate heavy nest predation causing limited juvenile
recruitment in Snapping and Blanding’s Turtle populations.
I captured 1834 individuals of five native and one introduced turtle species in
2022–2023 and compared my results with the results from Rivard and Smith (1973)
and Browne (2003). The objective of my thesis was to estimate population sizes and
compare community structure, relative abundance, sex ratios, and size structures
from 2022–2023 with 1972–1973 and 2001–2002 to determine the status of PPNP
turtle populations and the efficacy of the nest protection program. A total of 882
nests were protected between 2001–2021; 480 Snapping Turtle nests and 33
Blanding’s Turtle nests. I found an increased catch-per-unit-effort (CPUE) and a
more evenly distributed size structure with a significantly lower median MCL (mm)
than Browne (2003) for Snapping Turtles. I found a decreased CPUE and a size
structure with no significant changes since Browne (2003) for Blanding’s Turtles. [...] | en_US |
