Density Dependence and Adult Survival Drive Dynamics in Two High Elevation Amphibian Populations

Diversity

AmandaM. Kissel¹  Simone Tenan²  Erin Muths³ 

[1] Conservation Science Partners, 11050 Pioneer Trail, Suite 202, Truckee, CA 96161, USA;National Research Council, Institute of Marine Sciences (CNR-ISMAR), Arsenale, Tesa 104, Castello 2737/F, 30122 Venezia, Italy;U.S. Geological Survey, Fort Collins Science Center, 2150 Centre Ave. Bldg C, Fort Collins, CO 80526, USA;

关键词: Anura;    Pseudacris;    density dependence;    long-term data;    population growth rate;    per-capita recruitment;   

DOI  :  10.3390/d12120478

来源: DOAJ

【 摘 要 】

Amphibian conservation has progressed from the identification of declines to mitigation, but efforts are hampered by the lack of nuanced information about the effects of environmental characteristics and stressors on mechanistic processes of population regulation. Challenges include a paucity of long-term data and scant information about the relative roles of extrinsic (e.g., weather) and intrinsic (e.g., density dependence) factors. We used a Bayesian formulation of an open population capture-recapture model and >30 years of data to examine intrinsic and extrinsic factors regulating two adult boreal chorus frogs (Pseudacris maculata) populations. We modelled population growth rate and apparent survival directly, assessed their temporal variability, and derived estimates of recruitment. Populations were relatively stable (geometric mean population growth rate >1) and regulated by negative density dependence (i.e., higher population sizes reduced population growth rate). In the smaller population, density dependence also acted on adult survival. In the larger population, higher population growth was associated with warmer autumns. Survival estimates ranged from 0.30–0.87, per-capita recruitment was <1 in most years, and mean seniority probability was >0.50, suggesting adult survival is more important to population growth than recruitment. Our analysis indicates density dependence is a primary driver of population dynamics for P. maculata adults.

【 授权许可】

Unknown