|
" Southern Fox Squirrel (Sciurus Niger Niger) Foraging Behavior and Population Dynamics "
Huang, John
Welch, Shane
| Document Type
|
:
|
Latin Dissertation
|
| Language of Document
|
:
|
English
|
| Record Number
|
:
|
1055865
|
| Doc. No
|
:
|
TL54982
|
| Main Entry
|
:
|
Huang, John
|
| Title & Author
|
:
|
Southern Fox Squirrel (Sciurus Niger Niger) Foraging Behavior and Population Dynamics\ Huang, JohnWelch, Shane
|
| College
|
:
|
Marshall University
|
| Date
|
:
|
2020
|
| Degree
|
:
|
M.S.
|
| student score
|
:
|
2020
|
| Note
|
:
|
53 p.
|
| Abstract
|
:
|
The change in the interaction between southern fox squirrel (Sciurus niger niger) and eastern gray squirrels (Sciurus carolinensis) provided an opportunity to examine sublethal effects of predation as it relates to a species’ risk perception and habitat structure at two scales. The interactions allowed us to examine the evolutionary responses of the southern fox squirrel and eastern gray squirrel to predation risk reflective of their historically associated landscapes and habitat structures. Second, the succession of savanna woodlands into closed-canopy mixed forest provided an opportunity to assess the flexible behaviors of both species’ in response to changes in predation risks that occur with changes in current habitat structures (e.g., predation risks that vary within a patch). In this study, we quantified the foraging behavior and risk perception of the southern fox squirrel and eastern gray squirrel by compiling an ethogram from the camera footage obtained using a feed depot and a time-lapse camera. We expected southern fox squirrel vigilance behavior would have a positive relationship with change in canopy cover (i.e., vigilance behavior increases as canopy cover increases), whereas the vigilance behavior of the eastern gray squirrel would have an inverse relationship (i.e., vigilance behavior decreases as canopy cover increases). We expected southern fox squirrels would be more vigilant compared to the eastern gray squirrel. Contrary to our expectations, eastern gray squirrels spent a greater proportion of their foraging time being vigilant than southern fox squirrels. Our results were inconsistent with our predictions that vigilance behavior of southern fox squirrels would have a positive relationship with canopy cover, whereas eastern gray squirrels would have an inverse relationship with canopy cover. We failed to detect a significant effect of canopy cover on vigilance of southern fox squirrels and eastern gray squirrels. Our results suggest that eastern gray squirrels perceived greater risk from stationary and ambush predators, for whom vigilance is an effective strategy to avoid predation, than active predators, while southern fox squirrels perceived greater risk from active predators, for whom vigilance is less effective in avoiding predation. Conservation strategies for the southern fox squirrels have incorporated translocation efforts to augment and re-establish southern fox squirrel populations. Translocation has been used to successfully repatriate southern fox squirrel populations; however, none of these populations have been monitored long enough to examine recruitment and long-term survival. In our study we examined survival and recruitment of a repatriated population on the Marine Corp Recruit Depot – Parris Island (MCRDPI), South Carolina. Between January 2016 and July 2017, sixty-two southern fox squirrels were translocated onto MCRDPI, and were monitored using radio-telemetry and live-trapping efforts. We expected adult southern fox squirrel survival to be greater than juvenile southern fox squirrel survival. We also expected southern fox squirrel recruitment to be lower compared to other tree squirrel species. We used known fate models to estimate true survival probability. We modeled survival as a function of year, sex, season (to reflect differences in seasonal food abundance), stage (i.e., adult and juvenile), and squirrel mass. We used a Bayesian approach of the Jolly-Seber model as a restricted dynamic occupancy model to estimate recruitment. We failed to detect a difference between adult and juvenile southern fox squirrel survival. Only the survival model with year as a covariate was supported. Survival estimates were greatest in 2019 (0.73) and lowest in 2017 (0.23). Recruitment in 2016, 2017, and 2019 was 0.35, 0.43, and 0.22 respectively. Southern fox squirrel recruitment was low (0.22) compared to eastern gray squirrels (Sciurus carolinensis; 0.41), and high compared to red squirrels (Sciurus vulgaris;0.13). Our results indicated translocation as an efficient conservation tool for the long-term conservation of southern fox squirrels. Survival increased significantly after the two years post-translocation. Recruitment of our repatriated population was similar to those of the Delmarva fox squirrel, whose successful delisting can be attributed to its many successful translocations.
|
| Descriptor
|
:
|
Behavioral sciences
|
|
|
:
|
Biology
|
|
|
:
|
Ecology
|
|
|
:
|
Wildlife conservation
|
|
|
:
|
Wildlife management
|
| Added Entry
|
:
|
Welch, Shane
|
| Added Entry
|
:
|
Marshall University
|
| |