Last week Kyra blogged about our trip to Ventura to try to recapture Pelican N-12, one of the control birds from the Refugio pelican post-release study. While the satellite telemetry aspects of the project have provided a huge amount of information on these birds, the companion efforts by OWCN and International Bird Rescue to get the public to report sightings of pelicans with green or blue leg bands has also been quite successful.
In some areas like Half Moon Bay it has almost become a sport, with individuals and bird- and whale- watching boats constantly on the lookout and trying to get close for a clear photo of the band number. We greatly appreciate everyone who has reported birds and made their contribution to our study, but we also want to remind everyone that getting too close can be harmful not just to the animal you are focusing on but also others nearby. In some cases, like nesting plovers or terns, there are obvious signs to help you avoid disturbing birds.
It may seem like pelicans have an easy life, just sitting on the pier or breakwater all day sunning themselves. Some might even think that getting them to fly a bit is good exercise. But like many wild animals, a pelican’s ability to find food versus their energy expenditures are often very finely balanced. As you can imagine, with a bird as large as a pelican, getting up into the air can take a fair bit of effort. If that effort results in a new fish in the belly or avoiding being injured or killed, I think we would all agree it was worth it. But each time there is an energy cost to each bird. When people, dogs, boats, or anything unfamiliar gets too close, birds will try to move farther away, just like we do when someone we don’t know or don’t like gets right up in our face. And when they are resting and hanging out together in large groups like on a beach or a breakwater, they may fly without a direct threat but just because other birds do.
Even if they don’t fly, their heightened vigilance may keep them from normal rest or preening activities.
A 1997 study “Buffer zone distances to protect foraging and loafing waterbirds from human disturbance in Florida” found that brown pelicans disturbed by a walking human flushed at just under 30 meters, and recommended a buffer of 100 meters for approach on foot. The recommendation for motor boats was 120 meters.
While in some situations it is possible to get closer to wild birds without disturbing them, especially with special techniques or equipment, in most situations it is best to give them plenty of space. Use binoculars, spotting scopes and telephoto lenses to record and report band numbers. As Hippocrates wrote “First Do No Harm”.
And thanks again for keeping an eye out for colored bands.