The latest paper from SongBird Survival’s Keith Duckworth project has recently been published in Ibis.
PhD student Hugh Hanmer has been studying urban bird ecology and conservation with Professor Mark Fellowes and Dr Rebecca Thomas at the University of Reading. The primary focus of his PhD has been on the indirect effects of garden bird feeding, though other work has taken in nest boxes and domestic cat ranging across the urbanisation gradient.
Hugh’s recent paper investigates whether feeding birds increases local nest predation. Using the university’s suburban parkland campus as a study site, Hugh replicated a typical suburban garden. He set up artificial nests, containing quail eggs, either 5 or 10 meters away from feeding stations. A variety of feeder types were used (guarded/unguarded, peanut-filled/empty), and both the nests and feeding stations were monitored with camera traps to see which species visited them.
Hugh found that Eurasian magpies and grey squirrels were frequent visitors to unguarded feeders, and this resulted in a five-fold increase in predation rates of nests that were set up near these feeders. Eurasian jays also predated these nests, although they did not visit the feeders.
The researchers suggest that magpies and grey squirrels are attracted to the food, and then forage locally, increasing the chances of finding local nests, and that the Jays respond to the presence of the other species, rather than the presence of the food itself.
Irrespective of the behavioural underpinning, the result of providing food was increased nest predation.
Wildlife gardening is hugely popular in the UK, and we spend £200 million on bird food every year. But we need to ensure that we are doing the right thing for wildlife.
Hugh’s research has important implications for how we feed the birds in our gardens, to make sure we are benefiting song and other small bird populations.
Hugh suggests that feeders are placed as far away as possible from potential nests sites during the key nesting period in late spring. It’s also important to offer food which is less attractive to nest predators and more suitable for the birds we want to support. Finally, he advocates the use of feeder guards, even though this didn’t reduce predation. This is simply because the use of guards means that more food goes to the target beneficiaries, rather than helping grow local populations of squirrels and magpies!