Spurting and Filter Feeding Behaviors of a Juvenile Red-necked Stint (Calidris ruficollis)
by Bryce W. Robinson
Apart from its scarcity and place as a formidable ID challenge, juvenile Red-necked Stint (Calidris ruficollis) is an excellent late summer encounter in Alaska because of its focus on feeding and building fat stores for migration. This focus makes the stint a great subject for close proximity observation, photography, and video. Interactive birds that tolerate your respectful but close proximity are the most fun.
While taking advantage of one such bird, I noticed a somewhat atypical feeding behavior. I was able to capture the behavior in the clip above, as the bird sifts through the water, filter feeding in a way, and consumes small items when it happens upon them. I’ve seen this before in other peeps, but it is certainly an uncommon feeding behavior.
Spurting is an even more uncommon feeding behavior, but one that is regular in many shorebird species (Fellows 2013). Fellows (2013) offers the following description of the behavior: “the bird dips its bill into the water for a couple of seconds, or sometimes a bit longer, presumably to obtain food. It then withdraws its bill and slightly pushes its head forward, usually (though not always) with the bill lowered and then ejects or spurts a stream of water, as if ridding itself of surplus liquid taken in while feeding underwater. The bill is then reinserted in the water and the sequence is repeated“.
I’d never seen anything spurt before until I watched this juvenile Red-necked Stint filter feed in shallow water this summer. Unfortunately the video above doesn’t capture anything but filtering, but I was able to manage a decent photo of a spurting event.
I feel quite fortunate to bear witness to spurting behavior. Special thanks to my friend Luke for not only knowing the name of the behavior, but also letting me know of a note that names and details the behavior in shorebirds (Fellows 2013). Excellent behavior and excellent birding.
Fellows, B. 2013. Spurting Behaviour in Wading Birds. Wader Study Group Bulletin 120(3) pp. 208-209