Overview

The goals of this article were 1) to verify the uniqueness of the 2012 Razorbill invasion of Florida waters, 2) to hypothesize possible causes for this unprecedented event, 3) to find at least one possible source location and the possible mechanism which triggered this Razorbill event, 4) to search for some evidence to support the hypothesis, and 5) to meet scientists and others who would collaborate with us on this and future investigations of seabirds and the marine ecosystem. We believe we made good progress on these five goals (including "connecting-these-dots") and thank all those who worked with us on this.


In late 2012 thousands of seabirds called Razorbills (Alca torda) left their normal range along the northeast continental shelf and invaded Florida offshore waters for the first time, ever! Florida bird observation records going back to 1900 and earlier showed nothing at all like this had happened previously. This unique event raised many questions. How big was this event? How unprecedented was it? Why did it happen? Will it happen again? Where did these birds come from? Is this event "telling us something", and what? Were there other changes correlated with this in 2012 or leading up to 2012? Did some other changes cause the Razorbill invasion?

Bird observers were the first to detect this surprising event, and to realize how unprecedented it was. They were also first to be concerned that it might signal something else, some change in the ocean, but what? To address this they needed a collaborative investigation with marine ornithologists and scientists from other disciplines. This investigation has started, but is a long way from completed. This article gives an update of some of the work and the discovery being done, trying to find a possible plausible chain of dependencies, hypothesizing what that chain might be, working backwards from Razorbills, back to the Atlantic Herrings which they eat, back to zooplankton which the herrings eat, back to photosynthetic phytoplankton which the zooplankton eat, back to ocean temperature changes, and back to air temperature changes. This investigation is looking for a "smoking gun", actually for a chain of them, and thanks to collaboration with scientists in different disciplines it looks like the hoped-for pieces of evidence are falling into place, at least enough for us to have a plausible working hypothesis.

What maybe unique in this paper is 1) its use of the complete Audubon Christmas Bird Counts (CBC) database to find a possible geographic source of the Florida Razorbills, by comparing Razorbill numbers on all CBC circles, going all the way back to 1900, and 2) its proposal of the Bay of Fundy's extreme tides as a major contributor to the above-average heating of the Gulf of Maine GOM and perhaps the western North Atlantic (see hypothesis point 3 below). Having found a possible source of some of these birds in the northern GOM (in and around the Grand Manan CBC circle, where Razorbill numbers were anomalously low in late 2012, and in the adjacent Bay Of Fundy BOF), we sought other data from that particular area which might confirm the hypothesis, including 2012 water temperature, plankton, and especially a 2012 reduction in fish abundance which might be causal in driving some of the Razorbills in that area to seek other areas for food. We found evidence for each link in that chain (much of it from the RARGOM 2013 conference), plus recently discovering a striking 2012 drop in Atlantic Herrings caught in the fisheries in and around the Grand Manan area that year. We interpret this chain of evidence as supporting our hypothesis.

We are thankful for helpful collaboration from amateur bird observers, professional ornithologists, marine biologists, other marine scientists, the fishing community, the National Audubon Society, NOAA, and many other contributors/organizations. We benefited from this growing cooperation and hope it continues to grow, including a new central directory to the locations of relevant information across these domains, as suggested at the end of this article.