Seaside sparrows caught between predators, rising seasLeave a Comment
Posted: 12 Jul 2017 04:28 AM PDT read full story at ScienceDaily
Sea-level rise is a problem for saltmarsh birds, but so is predation, and birds sometimes find themselves caught between two threats: They can nest lower in vegetation to avoid predators, putting them at risk of flooding, or move up to keep dry but risk getting eaten. A new study finds that pressure from predators increases flooding risk for seaside sparrow nests — but that protecting them from predators could also mitigate the effects of climate change.
“Nest predation rates are so high right now that even under extreme sea level rise conditions, more nests are likely to be eaten than flooded,” says Hunter. “However, predation and flooding threats act synergistically, meaning that any estimates of the negative effects of sea level rise on the nesting success of Seaside Sparrow or other species are likely underestimates if they do not also consider the negative effects of predation on flooding risk. The flip side of this is that management actions to reduce nest predation could also reduce the risk of nest failures from flooding.” If measures such as fencing nest sites to exclude predators are taken, birds may place their nests higher in the salt-marsh vegetation, avoiding flooding from extreme high tides.
…”Regardless of the threat, it is increasingly clear that tidal marsh birds and their habitats are in trouble, and that we need to explore a range of potential solutions to find ways to help them persist in light of the many ways that humans are changing coastal habitats”…
Elizabeth A. Hunter. How will sea-level rise affect threats to nesting success for Seaside Sparrows? The Condor, 2017; 119 (3): 459 DOI: 10.1650/CONDOR-17-11.1