age structure

In recent years, commercial paddlefish harvesters have renewed their requests for opening a potential commercial paddlefish (Polyodon spathula) season in Alabama reservoirs of the Tennessee River, including part of Pickwick Reservoir, all of Wilson and Wheeler reservoirs, and the majority of Guntersville Reservoir. These reservoirs of the Tennessee River once supported robust stocks of paddlefish; however, beginning in the 1940s overexploitation became evident as the number of paddlefish harvested declined. Because of this widespread overharvest, a commercial and recreational...

White-tailed deer (Odocoileus virginianus) are one of the most abundant and well-studied ungulates in North America. Few studies, however, have examined how population demography affects the fawning season, which may be influenced by age structure and adult sex ratio of the population. From 2010 to 2013, we used vaginal implant transmitters (VITs) to record the birth date of fawns born within a 174-ha captive facility to elucidate how population demography affects fawning season. We documented an earlier shift in fawning season as male age structure increased from a mean of 2.74 years old...

Alligator gar (Atractosteus spatula) exhibit many characteristics of a periodic life-history strategy, including extended longevity, late maturity, high fecundity, and variable recruitment success. Observations of alligator gar spawning events indicate that recruitment in inland waters may be linked to spring and summer flood pulses and the availability of floodplain spawning habitats. However, because data have mostly come from observation and not formal experimentation, it is unknown whether these data represent true requirements or if they simply reflect conditions that were easily...

Historical eradication efforts, increasing fishing pressure, and growing anthropogenic impacts have resulted in decreased abundance or extirpation of the alligator gar (Atractosteus spatula) throughout much of its historic distribution. Current population status has prompted states to actively manage stocks; however, efforts are hindered by a lack of data necessary to make informed management decisions. To begin addressing these data needs, we investigated alligator gar population dynamics and exploitation in Choke Canyon Reservoir, Texas. A total of 754 fish (total length [TL] range, 678...