Our fish and the birds

[mitten]

Hi guys-

Growing up suburban and sixties, birds of prey were never seen except in the weekly reader and on nature shows with Marlon Perkins. As times changed and the environment got a bit cleaner, and I moved out of housing and onto land, birds of prey became more common and were a huge thrill to me. Now I live on a sandhill crane migratory path, within 10 miles of a blue heron protected rookery, have had green herons nesting in the field trees next door, see hawks every day, and occasionally see falcons.

As an innocent I was shocked when I first saw Floridians chasing away herons with a broom so they wouldn't eat the lizards. At the time I knew nothing about koi and didn't care if anything was grabbing frogs from the pond, it was, after all, The Environment. I now keep nets on every pond all the time. Probably I could be convinced to shoosh a heron away from my lizards, if I had any. There has been a change in how I see them birds now that I keep them fish of ours.

A question has been forming in the rattle section of my brain and it is time to ask it, hoping that someone will know. We have been starting to see bald eagles locally. Man are they big! Too cool. Their recovery from near extinction, or romanticized near extinction at least, seems to be accomplished and maybe now they will become a threat again. The osprey in Florida are numerous and thrilling but can often be seen flying carrying sizable fish. So, this has led to my question.

Will bald eagles take fish? from ponds? at my house? What would you do to prevent any pond robbing?

Mickey the windowman

[Valarc]

I don't know about your pond, but I used to do a lot of camping and boating on the susquehanna river, which for several years had one of the few mated pairs of bald eagles in the state nesting on one of the warning piers. It was fairly common to see one of the big parents swoop down to the lake and take a decent sized carp or bass. They were moving FAST when they did this though, so I would think it would take quite a bit of open space for them to be able to swoop and dive. If there are a few trees around your pond or it's close to the house I wouldn't worry too much about the eagles.

[MikeM]

From what I have read, fishing raptors, such as eagles and osprey, need flight room to swoop in on the waterbody in which their prey reside. They rely on their superb vision. A cover of trees, shade cloth, shade sails, screening, etc. interferes with both their line of sight and flight zone. Smaller carnivore birds, such as kingfishers, can be a greater worry in the areas where they nest.

The one fish-eating bird I've not read something about attacks on koi ponds is the anhinga ... which, for those who are unfamiliar with them, dive into water and are able to swim underwater to catch fish. I'd guess that most koi ponds are too shallow for diving. ... but I'd expect breeders to have problems with anhingas.

[mitten]

The anhinga sounds a lot like a cormorant. Cormorants have now traveled north and are here in some of our Michigan lakes so the bass guys are griping and fearful. The herons have landed on my nets and they have held so I'm not worried about them or cormorants. Herons will sit on my roof making the dogs go crazy and slide greasy white poop in a streak down the front slope so I can know they were here. The size of the eagles had worried me because I thought that the nets wouldn't be a match for them. Thanks for letting me know about the stretch of flying room they would need for fishing, hadn't thought of that. Are kingfishers the little cocky looking guys, brown tan and white with black curved beaks?

[kingkong]

Cormorant, remeber C or curved bill. This bird has the hooked bill
Anhinga has a staight pointed bill
Kingfisher is bluish-grey with white neck and underparts, large head with a thick black bill and a ragged crest

[luke frisbee]

Mitten my kitten,
no worries from bald eagles as they do have a flatter dive when they hit fish, And eagles won't go deep for a fish, and need a considerable space after they've nailed a fish to get back to altitude.... Eagles scavenge better'n any other bird of "prey", or they will force an osprey to drop the fish they have caught.
But ospreys DO NOT need much room to dive and will go deeper on their plunge. After an osprey goes in the drink they can get out of the water and shake similar to a dog to get the water off them and then start gaining altitude

[bekko]

Cormorants and anhinga need a lot of room to take off - probably 15-20 feet or so. They sort of flap their wings and kick the water surface with their feet to get air bourne. Cormorants may come in flocks and fish in fresh- or saltwater. Anhingas are usually solitary and fish in freshwater swamps. One species of cormorant is the one they use for fishing in Asia. You've seen the pictures. They put a ring around the birds throat so it cannot swallow and then tie a leash to it. The bird dives down to catch a fish and resurfaces. The fisherman pulls the bird back on-board with the lease and it then spits out the fish.
We used to have to weigh and measure random samples of fish from production ponds to monitor growth rates. I always thought it would be cool to have a pet cormorant to catch the fish for you.

-stevehopkins