UNH scientists develop method to estimate New England cottontail populationMay 20. 2018 10:39PM
DURHAM — Scientists with the New Hampshire Agricultural Experiment Station at the University of New Hampshire say they have developed a method to estimate the abundance of New England cottontail populations.
“Tremendous conservation efforts have been ongoing on behalf of the species, primarily in the form of the creation and restoration of thousands of acres of shrubland habitat over the last decade,” experiment station researcher Dr. Adrienne Kovach said in a news release.
Kovach, an assistant professor of natural resources and the environment, said to conserve a species, it is essential to know its population status and to be able to monitor it to detect trends over time.
“Our work provides the methodology to measure abundance and therefore an approach for monitoring trends and response to management in the future,” said Kovach in the news release.
He collaborated with Dr. Thea Kristensen, who is the first author on the paper and worked on the project as an experiment station supported postdoctoral researcher. She now teaches at Amherst College.
According to Kovach and experiment station researchers who have been studying the New England cottontail, there has been an 86 percent decline in the distribution of the New England cottontail over the last several decades.
In addition, the New England cottontail has lost more than 80 percent of its habitat over the last 50 years as people have developed the landscape and as areas of shrubs and young trees have grown up to become mature woods that don’t offer enough ground-level vegetation for cottontails to find food and hide from predators, according to The New England Cottontail Conservation Initiative, of which UNH is a part.
“The loss of young forest and shrubland habitats has implications not just for New England cottontail, but also for other species that depend on these habitats, including shrubland birds and pollinators. Many of these specialist species are on decline,” Kovach said.
Kovach and Kristensen developed a method to estimate the abundance of New England cottontails on habitat patches using a non-invasive genetic monitoring approach. They used the DNA obtained from cottontail fecal pellets collected during winter surveys to identify individual rabbits. They then constructed histories of the “captures” of these individuals and used that in a mark-recapture framework to estimate the abundance of cottontails, according to the news release.
Kovach described New England cottontails as “a rare and secretive species” that is difficult to monitor.
“Here we developed an efficient and effective survey design for sampling cottontail pellets in conjunction with the analytical framework for population estimation. Specifically, we determined the level of survey effort needed by field biologists to collect sufficient data for precise and accurate population estimates,” Kovach said.
“Going forward, this new estimation method will be integrated into ongoing conservation and monitoring activities for the New England cottontail. Specifically, this method can be used to assess cottontail population status and measure the response to habitat management and restoration,” Kovach said.
Kovach said researchers do not know how effective the habitat restoration effort has been in restoring the cottontail rabbit.
The research is being published in the journal “Ecosphere.”