On The Fly

At the Parker River NWR on Plum Island in Newburyport MA I was hoping to find a sampling of new migratory arrivals. The weather was cool,dull,and dreary, which I think had a pronounced affect on the migrants-because there were very few to be found. After traversing the entire length of the island I settled on a spot by the side of the road near some wetlands and watched several birds feeding. This I think is a tree swallow, and a very hard subject for a novice such as myself to shoot in flight. This image was taken from my vehicle as I was trying to pan under fairly poor light.
This was a real challenge for me for several reasons, least of which is the speed of these birds! I think the shot would have been a tad sharper had I been able to increase SS, but 1/1600 was as fast as I could go without pushing the ISO further.
I greatly appreciate any feedback on the shot as this is my first BIF attempt and post.

Thanks for looking and commenting.

D300
300 f2.8
TC-14E II
1/1600 sec @ f4
ISO 1000