Wednesday, December 26, 2012

Razorbills in Long Island Sound

It seems that the 2012-2013 fall and winter season will be duplicating much of the incredible 2011-2012 alcid season. This consists primarily of reports of Razorbills moving in Long Island Sound on a regular basis that are being seen and enjoyed by birders in Connecticut and New York. These birds are doing more than flying by at a considerable scope distance with sometimes several individuals near the shore swimming, diving, preening, and resting. A few years ago I would have been utterly thrilled with seeing just one bird a half a mile away as a little blur moving through my scope for several seconds. Now our standards have changed nearly overnight and seeing one flying out in Long Island Sound in such a manner is just like checking off any other common type of waterfowl. It's still very exciting to see them up close though!

Using eBird data and mapping capabilities we can easily examine graphically how the population of Razorbills has suddenly jumped into Long Island Sound. There have not been extremely high numbers reported, and most sightings are of one, two or occasionally several birds at most in a given spot in one day, so while we cannot see quantity on these maps, the focus is more on occurrence and the change in number of sightings overall. If you're interested in how they are moving up and down the Atlantic coastline, invading Florida (!) in unbelievable numbers that boggle the mind, check out this piece by the eBird team. It contains some fascinating thoughts on sea surface temperatures that may influence prey abundance and where the birds are foraging, and this may tie in to some of our sightings as well.

Here is an image of the Razorbill sightings so far this fall and winter from October (basically none) to December (where most come in) depicting the strong start to the season that should go well into 2013. The orange arrows indicate sightings within the last 30 days, and I took the screenshot of the selected data today on December 26. Larger arrows are birding "hotspots" while smaller ones are personal locations.

This is a look at the data from the 2011-2012 season showing how well we did last year. With a few months to go and more pelagic trips to be taken this year's map should fill in and correlate well to this one.

The 2010-2011 map shows a very noticeable lack of sightings along the Connecticut coast compared to the previous two years. However, there are definitely birds in the area and plenty moving around just outside of Long Island Sound, albeit reduced in number.

This does not last for long as the 2009-2010 map shows an astonishing lack of birds in the waters of Long Island Sound with fewer sightings in neighboring states and in the nearby Atlantic waters as well.

What a change! The only Connecticut sightings are focused around New London at the entrance to Long Island Sound, and Montauk Point is as far as the birds make their way into the New York side of the Sound as well. Occurrence decreases all over the map. Jumping back one more year to 2008-2009 shows us what is almost like a do not enter line from Long Island to Block Island to eastern Rhode Island, and even fewer sightings overall again.

Take a look at this final map - there are a few more sightings on it as you would expect considering it is of all the Razorbills logged into eBird with dates from 1900 to 2007!

One of the problems with an examination like this one is the decrease in observers compared to now as we move backwards in time. Obviously no one was punching in their data in the early 20th century, but there are many records that have been put into the database from past decades across the country. Connecticut Audubon Society has added thousands of historical records from our state to enhance eBird data and save these valuable sightings in a secure and permanent database. While there were fewer people eBirding in 2007 or 2009 than today, there were plenty of users who would have been logging Razorbills or entering records of them several years ago, myself included. There are many other folks that I know who regularly eBird their older sightings, having meticulously recorded every birding outing, and eagerly enter species like this one as soon as they can. Yet there are only a handful of records in over 100 years in the above image, and the 2008-2009 season had precisely zero birds.

As said initially, these maps generally portray an enormous shift in the population of wintering Razorbills in and around Connecticut's waters in an obviously very short amount of time at what appears to be an utterly unprecedented level. It is believed that shifts in their prey abundance has led them to venture into these new waters, and as more birds find more plentiful food they return to the same area throughout the season and into the next, occasionally with others in tow. The eBird team's explanation of warm waters in their typical winter range probably impacts us as well as some of those birds seeking better feeding areas enter Long Island Sound, too. Razorbills seem to be feeding almost exclusively on small fish, and perhaps prey levels are on the increase in the Sound due to human improvements in water quality and fishing. Northern Gannets are frequently cited as another once extremely rare bird that is now regularly found in Long Island Sound numbering sometimes into the dozens in several months of the year. Perhaps more Razorbills are being seen or forced into other waters because there are so many more of them as populations recover or spike due to higher levels of prey, almost like the Snowy Owl flight last season believed to be due to a "bumper crop" of small mammals. That would certainly be the most optimistic and welcome reason!

Climate change has been modifying the Sound already with more southern species found there in the summer and unexpected population shifts in all seasons. Combined with anomalies in their wintering areas Razorbills may see our area as what theirs used to be. I have noted that this season most of my sightings on calm and pleasant days, outside of strong storms that move birds around on a higher scale, have been of Razorbills feeding near shore in frequently utilized areas. They seem to favor the same spots that possibly have a strong food supply. Additionally, these birds are not flying in to the area in the early morning and leaving in the later day as they had much of the time in previous years. They appear to be spending their time and wintering lives here with us at this point, at least in my experience. Considering all that has happened for the species along the Atlantic Coast and Florida's superb sightings this may become the new norm...or it may change rapidly once again. Either way, as the eBird piece notes, it seems doubtful that any of this is good for the species, and the added stress may take a high toll. Many of these unknowns may be answered in time, and eBirding your Razorbills along with all of your sightings will help paint the picture for us.

Watch the shore in the next few days during and after the strong nor'easter that is about to impact the region with snow, sleet, rain, and winds gusting to over 60 MPH. These systems literally push alcids and other rarities directly into Long Island Sound. With a few Dovekie sightings here and there in the area a storm like this one is probably the best chance to find one in Connecticut waters. Other oddities can be had as well from more Common Eiders to Black-legged Kittiwakes or even other extremely rare alcids.

Scott Kruitbosch
Conservation Technician

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