The role of behavior in tern conservation

Abstract

Behavioral research has long had an important role in the conservation of terns (Aves: Sternidae). Habitat management and restoration of breeding colony sites depends on knowledge of the cues used to select colony and nest sites. For example, conspecific attraction with playback and decoys is commonly used to bring terns to suitable colony sites and habitat modification is often used to increase the availability of suitable nest sites. Tern colonies are interconnected by dispersal, and a metapopulation approach is needed for effective management. Population dynamics are therefore affected by behaviors that influence the frequency of movement among colony sites: site fidelity, natal and breeding dispersal, and group adherence. The monogamous breeding system of terns should keep effective population size similar to census population size, but variation in sex ratios (likely resulting from sex differences in behavior) and in parental quality can result in a smaller than expected effective population size. In addition to the behavior of terns, knowledge of the behavior of predators on terns contributes to management plans, because predator behavior can sometimes be manipulated and predation is often performed by only a few specialized individuals. Other examples of links between tern behavior and conservation are also briefly reviewed, such as behavioral toxicology research and studies of behavioral responses to human disturbance and manmade structures. More work is needed on the behavior of migratory terns at staging sites, stopover sites and wintering grounds, and on the behavior of less well-studied species and species in less well-studied geographic regions [Current Zoology 60 (4): 500-514, 2014].

Migratory routes and wintering locations of declining inland North American Common Terns

“…Climate change is currently identified as one of the greatest threats to Common Terns worldwide (Cabot and Nisbet 2013, Palestis 2014, Nisbet et al 2017. Issues related to climate change-including increased severity of storms, changes in food availability, and rising water levels-are important factors that may negatively affect Common Terns throughout their annual cycle (Cuthbert et al 2003, Cabot andNisbet 2013).…”

Animal behavior can inform conservation policy, we just need to get on with the job – or can it?

“…So why is it that these two disciplines rarely merge, despite now being the discipline of Conservation Behavior in its own right? This disconnect and where it occurs has been identified by Palestis(2014), and multiple times by Caro (e.g., 1999Caro (e.g., , 2007, whom contribute to this special column. Both Palestis (2014) and Caro (2007) suggest that behavioral ecologists have been "slow to link with conservation biologists" (Palestis, 2014).…”

“…Consequently, out of curiosity and a touch of skepticism that these disciplines rarely merge, I ran a simple analysis, finding that Caro (1999Caro ( , 2007 and Palestis (2014) seem to be correct. For this analysis, I did a search on Web of Science™ (Table 1), looking up the search terms "ethology", "animal behavior", "behavioral ecology" ('behavioral terms'), and "conservation biology", both in conjunction and independently, for the past 30 years, from .…”

“…Within the seven contributions to this special column, the broader implications and difficulties pertaining to research exploring the relationship between behavioral and conservation-based research are readily evident in two review contributions, which also provide helpful guidelines for researchers in the area, as well as constructive areas for further research (Caro and Riggio, 2014;Palestis, 2014). Berger-Tal and Saltz (2014) discuss how GPS technology serves as an aid to managers post reintroduction of animals, and provide data from fallow deer and from oryx to support their argument.…”

“…Most species of terns are on the national, state or province conservation lists, and Brian Palestis (2014) discusses the role of behavior in tern conservation across the globe. He identifies current and future threats to these birds, and what can be done to mitigate these threats, in particular highlighting that, as colonial breeders, appropriate management can benefit a large number of individuals.…”