Geology topics

Lindsey M. Phillips

Publications and source records attributed to Lindsey M. Phillips.

2 recordsLinked to original sources

USGS2025

Comparison of methods for estimating wild turkey poult survival

Eastern wild turkey ( Meleagris gallopavo silvestris ) population growth is driven by variation in reproduction, and poult survival is a crucial vital rate. Traditional poult survival monitoring uses flush counts of radio-tagged females, but brood flocking (when broods and females merge into larger flocks) and mark retention are potential problems with this method and can produce biased estimates. Alternatively, radio-tagging poults to estimate survival offers a potentially less-biased method if tagging and tracking poults can be conducted without adverse effects on the poults. We compared poult survival estimates derived from flush counts and from radio-tagged poults over a 56-day monitoring period during 2018–2022 in south-central Tennessee, USA. We radio-tagged 183 poults and monitored 85 broods via 2-week flush counts and observed 572 individual poults during flush counts over the 56-day monitoring period. We used known-fate survival models for the telemetry data, Lukacs survival models for the flush count data, and a modified known-fate model to estimate whether radio-tagging poults affected their survival. Two-week survival estimates from the flush count of broods, and radio-tagged poults were similar (flush count: day 0–28: 0.25, 95% CI: 0.20–0.31, day 29–56: 0.56, 95% CI: 0.36–0.76; radio-tagged: day 0–28: 0.30, 95% CI: 0.23–0.37, day 29–56: 0.68, 95% CI: 0.49–0.87). Using known-fate survival models, radio-tagged poults had similar survival rates to non-tagged poults within the brood (day 0–28: Ŝ Radio-tagged = 0.15, 95% CI: 0.10–0.20 v. Ŝ Non-tagged = 0.20, 95% CI: 0.16–0.23), which suggests the radio-tags did not directly affect survival. However, survival of individuals that were trapped was lower than survival of broods that were not trapped during the first 14 days. Trapping methods may need to be adjusted to limit incidental capture effects when choosing to use radio-tagged poults. Conducting flush counts every 14 days until day 56 of the brood-rearing period likely is the most cost-effective method for estimating poult survival. However, monitoring individual radio-tagged poults may yield additional information, such as cause-specific mortality, that may better inform management.

Tennessee↗

USGS2024

Assessing wild turkey productivity before and after a 14-day delay in the start date of the spring hunting season in Tennessee

Ten state wildlife management agencies in the United States, including six within the Southeast, have delayed their spring wild turkey ( Meleagris gallopavo ) hunting seasons since 2017 by five or more days to address concerns related to the potential effects of hunting on wild turkey seasonal productivity. One hypothesis posits that if the spring hunting season is too early, there may be insufficient time for males to breed hens before being harvested, thus leading to reduced seasonal productivity. We conducted an experiment to determine whether delaying the wild turkey hunting season by 2 weeks in south-middle Tennessee would affect various reproductive rates. In 2021 and 2022, the Tennessee Fish and Wildlife Commission experimentally delayed the spring hunting season to open 14 days later than the traditional date (the Saturday closest to 1 April) in Giles, Lawrence, and Wayne counties. We monitored reproductive rates from 2017 to 2022 in these three counties as well as two adjacent counties, Bedford and Maury, that were not delayed. We used a Before-After-Control-Impact design to analyze the proportion of hens nesting, clutch size, hatchability, nest success, poult survival and hen survival with linear mixed-effect models and AIC model selection to detect relationships between the 14-day delay and reproductive parameters. We detected no relationship ( p > .05) between the 14-day delay and any individual reproductive parameter. In addition, recruitment (hen poults per hen that survived until the next breeding season) was very low (<0.5) and did not increase because of the 14-day delay. The traditional Tennessee start date had been in place since 1986 while the turkey harvest increased markedly until about 2006 and more recently stabilized. Our data indicate that moving the start of the hunting season from a period just prior to peak nest initiation to 2 weeks later, to coincide with a period just prior to peak nest incubation initiation, resulted in no change to productivity or populations in wild turkey flocks in south-middle Tennessee.

Tennessee↗