Category Archives: Posts

Sustainable hunting regulations take the speed of trophy growth into account

(c) Susanne Schindler

Hunting regulations aim to keep trophy hunting sustainable. Yet most regulations fall short of this aim and trophy size is becoming shorter over time in most hunted populations, such as Bighorn sheep, Impala, Mouflon, and Sable antelope. This might be due to ignoring the speed of trophy growth when deciding on hunting regulations.

more

Schindler, S., Festa-Bianchet, M., Hogg, J., & Pelletier, F. (2017). Hunting, age structure, and horn size distribution in bighorn sheep The Journal of Wildlife Management DOI: 10.1002/jwmg.21259

Regulating trophy hunting: antlers or reproduction?

(c) Jeremy Cusack (www.jeremycusack.com)

(c) Jeremy Cusack (www.jeremycusack.com)

Guest post from Rocío Pozo:

Imagine you are a trophy hunter. The red deer hunting season has just opened and you are ready to go out and get those trophies you have been waiting for. What would be the first question you would ask yourself? Exactly! What is the hunting quota?

more

Pozo, R., Schindler, S., Cubaynes, S., Cusack, J., Coulson, T., & Malo, A. (2016). Modeling the impact of selective harvesting on red deer antlers. The Journal of Wildlife Management. DOI: 10.1002/jwmg.21089

Daughter or son, which sex to produce?

Female bighorn sheep with her young.

(c) Peter Neuhaus

 

The right offspring sex can increase the number of grandchildren. Theory predicts which offspring sex is optimal depending on the mother’s condition, but mothers in natural populations do not behave according to theoretical predictions. We explain the reason for the mismatch and provide more accurate predictions.

more

Schindler, S., Gaillard, J., Grüning, A., Neuhaus, P., Traill, L., Tuljapurkar, S., & Coulson, T. (2015). Sex‐specific demography and generalization of the Trivers–Willard theory Nature, 526, 249–252DOI: 10.1038/nature14968

Age-pattern of death shapes population growth rate

A gravestone dated 1673 in Bochum, Germany (c) Markus Schweiss / Wikimedia Commons / Public Domain

 (c) Markus Schweiss / Wikimedia Commons / Public Domain

The age at which we die determines how fast our population grows. Recent work shows how to predict the growth rate of a population from the age-at-death distribution.

more

Schindler S, Tuljapurkar S, Gaillard JM, & Coulson T (2012). Linking the population growth rate and the age-at-death distribution. Theoretical population biology, 82 (4), 244-52 PMID: 23103877

Size, Sex and Squirrels

(c) Peter Neuhaus

(c) Peter Neuhaus

The body size of an animal influences its survival, fertility, and mating chances. In addition, who is reproducing and with whom determines how a species evolves. Despite the important fact that body size and mating decisions shape the population and the course of evolution, there have been limited methods so far to study how both together affect population growth.

more

Schindler, S., Neuhaus, P., Gaillard, J., & Coulson, T. (2013). The Influence of Nonrandom Mating on Population Growth The American Naturalist, 182 (1), 28-41 DOI: 10.1086/670753

New Species by Ladies’ Choice

(c) Glen Fergus / Wikimedia Commons / Public Domain

(c) Glen Fergus / Wikimedia Commons / Public Domain

Female animals who prefer healthy and fit partners are having more and fitter descendants. A gene that brings forth such mating preferences is going to spread quickly. This gene can even forward the split-up of one species into two.

more

Schindler, S., Breidbach, O., & Jost, J. (2013). Preferring the fittest mates: An analytically tractable model Journal of Theoretical Biology, 317, 30-38 DOI: 10.1016/j.jtbi.2012.09.018