November 30th –
Bob and I were joined on Crow Patrol at the Lawrence Winter Crow Roost by Susan Wrisley and Steve Bennett from NH, It was such fun. The crows gave us another pattern for the evening. There were strong NW winds and as we all watched from the New Balance Factory parking lot looking east, they came up in vast waves over the water tower hill and settled into the trees on the north side of the river, many continuing south over the old mill building on the south side of the parking lot – not up the river and over the bridge. Susan, Steve and I then left Bob counting the stream from the east and we went to the truck depot when there was little action and then out over the Casey Bridge where we turned north seeing waves streaming in from the north. We turned into Pemberton Park which is along the northwest side of the river just over the bridge.
Quite a few birds were sitting in the far trees along the river and many were on the ground and wires in front of the day care center. Time for a lesson on identifying American and Fish Crows in the field. That proved to be very informative and much enjoyed.
On to our favorite pull out just over the Rt. 28 bridge on the west side. No crows here tonight so we went back to the truck depot on So. Canal St. after picking up Bob (he had had 12,000+ crows from the east). They were beginning to stream in – many on the ground lit by the depot lights, many on wires, lots of fun, noise and crows everywhere.
December 1 –
Susan Brown of Andover called wanting to join us. Last night there was practically no wind and as we watched from the New Balance Parking lot crows began to appear over the water tower hill – very high up – and they streamed up very high over the New Balance Plant – NOT over the river. Bob soon left to count them from the Casey Bridge. More crows began to appear over the airport and move high to the south side of the river and over the New Balance Plant – Another variation!!!!!!
Susan and I then repeated the route of the previous night, passing Bob on the bridge and into Pemberton Park where there were only a few birds in the trees along the river. On to the RT. 28 bridge parking area where there were thousands of birds on the south side of the river which had just begun to lift off and head towards the roost. By the time Bob joined us (after it was dark), he had had 7,000+ birds from the west. Now back at the depot thousand of birds began pouring in from the rooftops of the buildings on the south side of Merrimack St. – stream after stream. There were none on the depot road and they all seemed to be streaming in over the National Grid lot towards the river.
The vast number of birds so far this year that are still piling into the roost totally blows my theory of why they moved out of the river roost last year from January to very late March. I had surmised that the thin line of trees along the river where they roost could no longer support their numbers as more and more migrants poured in. We do need to get counters lined up on both sides of the roost ON THE SAME NIGHT to be sure we are not double counting (as they may go in a different direction the next day having learned in the roost about a good food the night before).
CAN YOU COME AND COUNT?
We are also trying to find a researcher to lead a study where the crows get some satellite tags to know for sure where they are going in the day, what percent are migrants, and where they eventually nest. Blood and feather samples are also used to determine the bird’s geographic origins.
Do hope you’ll come and visit. It is quite a show.
Dana
Dana Duxbury-Fox
North Andover, MA
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