Every time I try to distance myself from this rep, it's friends like you who pull me back in to it...
That was funny though, thanks for the laughs....
Maybe I can help out with a few thoughts.......
Note...
Finchaser is the real bird expert, although he will flat out deny this....
I've been out tuna fishing with him and he spotted a small group of tuna chicks from a mile away, without binocs....pretty impressive when you consider these birds fly very close to the water.
He also can go on and on....an on....about any bird out there......much more than I can.....if you need a birdwatching guide, book him now....he has special Winter Rates.......
Blazin and others, good analysis and deduction. Some birds are lazy and in my experience tend to hang out where the most abundant source of food is. Looking at their behavior and figuring out what and why, has definitely helped me to catch more fish.
There are certain times of year when I analyze bird crap in key areas...it gives me clues as to what they are feeding on and if the seasonal forage I'm looking for is there in any numbers.
Cormorant/Loon Change-over......Finchaser already mentioned it and has talked about it in the past.
When the water gets colder and the season transitions into Winter, many of the cormorants leave and are replaced by loons. To me they are pretty cool birds, I love watching them...
These are what you most likely saw, in the area you were fishing....
Some of our Fall Saltwater Birds......
1. Cormorants:
I do kind of dislike the cormorants though...as they have decimated some key forage species in certain areas, and are hated for doing that. There are some communities where they have decimated the trout so badly that private citizens put a bounty on killing them. The problem is they will eat just about anything. If a juvenile forage fish population is in a fragile stage, they can, and have, wiped that population out of that area. I really don't like them, and think of them as the welfare cheats of the bird world. (JMO)
On my kayak trips to the LI Sound I see them by the hundreds on the rocky islands out there. They also like to hang out near bridges, canals, and inlets. They know when the fish are there, those areas will have the highest concentrations.
2. Loons:
As fin and others mentioned, they come in when the water gets cold as part of their Winter migration south. They are often accompanied by these small seagulls known as Bonaparte's gulls.
If you see birds swimming in areas and diving down this time of year, they are likely to be loons. (As opposed to gannets, which usually circle in the air, and have the remarkable plunge dives as their way of catching)
I remember trips to Quebec fishing for pike on remote lakes. A day was not complete unless you heard or saw one of these cool looking birds on the water. Their call has given birth to the phrase "crazy as a loon"...which is probably how some of the fishermen out there describe me...
Loon behavior - they will swim in the water with their heads just below, scanning for food....When they find it they dive down quickly and grab it. I never get tired of watching them. Right now they are likely feeding on sand eels but will eat many tiny things that move.
3. Bonaparte's gulls:
They often are found around loons when loons are actively searching for food. They will circle around them at times, knowing that they are good hunters. They use the loons to find areas where fish are most highly concentrated.
They summer up north, Maine to Canada, and are (usually) only found down in our area this time of year, on a migrational path down to Southern US, Gulf of Mexico, and parts of Mexico/Central America for the Winter. (you will also see more snowy owls in barrier areas this time of year as well, as they too make stops on their southern migrational path)
Bonaparte's gulls are one of the smallest gulls out there. The black head that they sometimes have, is not always apparent this time of year. They change a bit during the molting process and mostly look like other gulls, but with a black spot near the head.
They fly along above the water looking for small fish (IE rainfish, spearing, small sand eels). They sometimes dive in when they spot bait close to the surface or when foraging fish push it upwards in the water column.
**Learning about these birds and their behavior is a good way become a better fisherman.
I'm always poking and prodding around rocks, inlets, and sod banks, and bridges when I'm out there to see what forage fish are around. This knowledge is exciting to me. Letting birds do part of your scouting for you is a smart strategy for any fisherman who wants to catch more fish.