Thursday, March 12, 2015

Beach birds and beached birds

As if we needed any more reminders of just how sharp a knife edge life can be in the natural world, it seems we are beginning to see the down side of the rather brutal winter that we have been enduring. Our Wednesday morning walk this week took us along the South Cape May Beach - despite the sea fog whipping around the point. This proved to be a good move when we chanced upon a single Piping Plover that Tom Reed had found shortly before us - the first sighting of the year for Cape May and a sure sign that spring is heading into the next phase of its slow but steady progress.

However, what was less joyous was the discovery of a dead Red-necked Grebe and a dead Horned Grebe on the beach. Though this in itself is not unusual - nothing lives forever after all - it did make for some interesting discussion points on the walk and continued into a texting conversation after a number of other dead waterbirds were reported from Two Mile Beach. These included American Black Duck, Surf Scoter, Ruddy Duck and Greater Scaup in the mix. What really opened up the discussion was the discovery that a number of these birds had orange or red cable ties attached - one to each leg and one to each wing. A closer look revealed a numbered, metal disc attached to each corpse.

This all seemed very mystifying, but the treatment of these birds was uniform enough to suggest this was being done by someone with a purpose. Opening the conversation up wider, to our friends at various wildlife organizations, eventually got us to the interesting truth - and an opportunity for us all to get involved in something interesting. It turns out that the brightly-colored cable ties are attached to the dead birds by researchers from SEANET - the Seabird Ecological Assessment Network. This is all part of a long term study which began back in 2002 in Massachussetts, with research now covering the whole eastern seaboard of the USA. The project uses citizen science volunteers to patrol beaches on a regular basis and tag any dead birds that they find. The bird's location and species are recorded at the time, along with other information and the tags are primarily used to identify birds already counted in subsequent surveys. However, the tagging has other uses; it allows the bird to be individually identified such that studies can be made on such things as how long a dead bird might lie around before finally being eaten or decomposing; how far the corpse might be moved by ocean currents; and a whole range of other interesting things.

This male Greater Scaup at Two Mile Beach gives a good idea of what to look for. A brightly-colored cable tie is attached to each wing and leg of each dead bird found. This ensures that, if the body breaks up, pieces can still be identified for longevity purposes, while also making the bird readily identifiable as tagged should it get rolled over, half buried or otherwise moved around by the tides and/or wind [photo by Tom Reed].

Tucked underneath one wing, you may also find a numbered, metal tag which helps researchers identify the individual. If you are reporting a find, it is always worth checking for one of the tags and photographing it, or writing down the details to send to the SEANET researchers. Here's a tag on the same male Greater Scaup as above [photo by Tom Reed]

There is a lot of information on the SEANET project available on the web; you could visit the SEANET blog for much more on the background and some recent findings of the project, or go to the SEANET website, where you can hook up and become a volunteer if you so wish. There is some fascinating research being carried out by this group and, now when we see those strange birds with their colorful attachments - we can know that the SEANET team have been our way. If you do spot such a bird, do please leave it where it is, as the project relies on natural processes to give them the best data for their work. But you are encouraged to take a photo and report the bird to SEANET - for full details on how to do this, click here.

It seems likely that the brutal weather will result in an increase of dead birds being washed up on our bayshores and beaches; local fish and wildlife officer report data showing a noticeable drop in average body weights for a number of duck species in the back bays as a likely result of some very difficult feeding conditions this past couple of months. If you find a dead bird on the beaches that is not tagged, you might like to give Cape May Bird Observatory a call with details of the whereabouts of the bird. We have a license to salvage such individuals and they go to museum collections to be prepared and used as study skins for research. Nothing goes to waste if we can help it!

When you find birds like this Red-necked Grebe (left) and Horned Grebe (right) they might look like a lost cause as far as a usable museum skin is concerned, but a skilled hand can transform them - see the following photos of the same two birds, taken the following morning... [photo by Tom Reed]

Red-necked Grebe after drying and cleaning [photo by Mike Crewe]

Red-necked Grebe after drying and cleaning [photo by Mike Crewe]

Horned Grebe after drying and cleaning [photo by Mike Crewe]

IMPORTANT NOTE: Be aware that, in some instances, the corpses of freshwater birds may contain pathogens that can be harmful to humans. We do not encourage anyone without the correct permits and protective equipment to handle such dead specimens.

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