On West Park lake, one coot feeds another. I’m not sure why.
It could be an adult feeding one of its chicks. Coots are big on parental care. Both parents feed the chicks even when they have grown enough to forage for themselves. But surely not once the chicks have grown up enough to adopt adult plumage. The one being fed is somewhat smaller than the other bird, so might still be on of this year’s hatchlings.
Alternatively, this might be a pair of adults which were just beginning the process which might lead to trying to raise a brood: feeding as part of a courtship process. It was a bit late in the year for that, but perhaps not quite too late if, for example, this was a pair which had lost all the chicks from an attempt earlier this year. Coot chicks do suffer a heavy attrition rate, despite all the efforts of parental care.