Bird interactions

Mute Swans

Wednesday, August 26th, 2009

Feral Mute Swans are collectors’ items for Minnesota birders, but birds of a different feather in Michigan. My wife and I rode the ferry today that travels across Lake Michigan between Muskegon, Michigan, and Milwaukee. We saw about four dozen Mute Swans in the Muskegon harbor. There are several thousaned of these birds in Michigan. This is an introduced species, native to Europe and Asia but not North America. Mute Swans are aggressive birds, driving native waterfowl from lakes they choose for their use. Loon populations have been impacted by the swans. Lake-shore property owners in Michigan often petition to have the swans killed because of their aggressive habits toward both man and beast, and because the swans soil docks and swimming rafts. The Michigan DNR authorizes such kills, sometimes to the dismay of people who don’t understand the problem non-native species can cause. The population of these birds in the Great Lakes area is reported to be increasing from 10 to 20 percent per year. In Minnesota, the birds are classified as a regulated invasive species. Introduction into the wild is prohibited, and possession of captive birds requires a game-farm license and containment.

Regulatory classification (agency): Mute swans are a regulated invasive species, which means introduction into the wild is prohibited (DNR). Possession of captive birds requires a state game farm license and fencing to contain them.

Get outta here!

Monday, August 3rd, 2009

The blackbird in the photo is chasing a Swainson’s Hawk from its nesting territory. The hawk was just doing a flyover, but the small bird was taking no chances. Raptors do take songbird eggs and nestlings, so an investment in caution is a good idea. Swainson’s eat insects for most of the year, hunting down small mammals, reptiles, and sometimes birds only during the nesting season. Swainson’s Hawks are mostly birds of prairies west of Minnesota, although the bird is routinely seen in our state. They winter in South America, moving south in September and October, sometimes many together. I’ve seen a hay field in South Dakota with more than 100 Swainson’s Hawks working the cut grass for grasshoppers, fattening themselves for the migration flight. These birds were photographed recently in North Dakota.swainsons-chased-4-5021.jpg

Taking the babies for a ride

Tuesday, July 21st, 2009

Earlier this year I watched Western Grebes in their courtship dances at Sand Lake National Wildlife Refuge north of Aberdeen, South Dakota. Last week, in the same spot, I watched young grebes being fed atop a parent’s back. This pair of grebes had two young, both tucked beneath the wings of one of the parents. Sometimes you couldn’t see the small birds. Other times they had their heads and necks extended, mostly when food was offered. The non-carrying parent was fishing for minnows to feed them. What do you do with the babies when it’s your turn to fish? You just extend your wings and rise out of the water. The babies unceremoniously slide off, promptly climbing aboard the other parent. It didn’t look like the grebe chicks were ready for the change, and neither was I, my camera’s shutter speed not fast enough to capture a clear shot of the sliding chick. My favorite spot to watch these birds is the bridge where South Dakota Highway 10 crosses the Sand River in the northern part of the refuge. The river is wide here, lake-like, bordered by high reeds. The grebes fish in the water flowing beneath the bridge. They sometimes are as close to observers as 15 or 20 feet. Terns, gulls, pelicans, and cormorants also feed here.  west-grebe-family-low-rez-51491.jpgwest-grebe-feeds-low-rez-51431.jpg grebe-unloads-trib-5182.jpg  

Water ballet

Saturday, May 9th, 2009

We’re back from a week of birding in North and South Dakota. We began at Devil’s Lake, working our way south through Jamestown and down to Sand Lake National Wildlife Refuge in South Dakota. The amount of water on the ground is overwhelming. Every refuge or game preserve we tried to visit was unreachable because of flooded roads. Sand Lake NWR is pretty much under water. The lake is a wide spot in the James River, which begins north of Jamestown. Most of the water we saw in ND will have to flow through the Sand Lake refuge before it can return to normal. Staff there says that could be this fall. High water did not stop Western Grebes from courting, however. At the SD Highway 10 bridge over the James River at the north end of the refuge, a couple of dozen pair of grebes were courting. This was the first time ever that I’ve seen the water dance these birds do, the rush across the top of the surface. Time and location finally coincided. We parked at the bridge (truck traffic is terrible on this road), and watched the show from our vehicle. The birds danced not more than 50 feet from us. It was worth the trip. There is a lot of calling and posturing that precedes the dance. Then, boom, they jump up and run across the water for two or three seconds. Here are shots of preliminaries and the main event.west-g-dance-prelim-6899.jpgwest-g-begin-dance-6900.jpg  

Courtship finery

Wednesday, April 29th, 2009

The males of many bird species present their very best appearance during courtship. Hooded Mergansers become one of our most beautiful birds at this time. We found this courting male on a neighborhood pond Thursday afternoon. He was with two hens, one who apparently had accepted his wooing, a second who swam ashore and ran away whenever the excited male approached. He wasn’t a bit discouraged by her, displaying in courtship high gear, fluffing his headdress, puffing his neck, doing the head tipping and bobbing routine that is meant to demonstrate his fitness as a mate. Hooded Mergansers are not hard to find this time of year (small ponds in wooded areas are best places to look), but you’ve really not seen the bird until you see him courting.


Great Horned vs. Barred Owls

Sunday, January 4th, 2009

 owl-talons-0030.jpgDiscussing the Great Horned Owl that appeared in our backyard last week I mentioned that we have not seen nor heard a Barred Owl for several months. A Minnetonka birder discussing owls on an email network this weekend said that he is seeing Great Horned Owls in his neighborhood, but has not seen a Barred Owl there for some time, although in the past both species had been seen coincidentally in the area. Great Horned Owls are the most significant avian predator of Barred Owls. When horned owls move into a territory it is possible that the Barred Owls move out or are eaten by their larger cousins. While the two species of owls might look close in size, Great Horned Owls at three pounds weigh twice as much. The photo shows the foot of a Great Horned Owl. The talons have needle points. Note the texture of the inside of the foot. Those stipples have the texture of rubber, improving grip, as if the talons alone were not enough. The photo is of an owl found dead near Grand Marais several winters ago. It had been shot in the back. 

A Visit from an Owl

Tuesday, December 30th, 2008

great-horned-owl-7944.jpg  A Great Horned Owl was in our backyard this morning. It was brought to my attention by a pair of crows. They were harassing the owl, calling loudly, occasionally making short winged forays at the big bird. The owl sat calmly, facing away from me until I took a dozen steps from our back door. It then pivoted its head 180 degrees so I was looking at its back and its face at the same time (see photo). We haven’t seen or heard a Great Horned Owl here for some months, although for our eight years here there has always been at least one of these birds in the neighborhood. We are well into courtship season now (Great Horned Owls nest much earlier than other resident birds), so the owls are likely to be more vocal if not more active.  I’ll have to start paying more attention to night sounds, and hope the crows continue to do location work for me.

Crows know who you are

Tuesday, September 2nd, 2008

crow-american-head-good-0945.jpg  Magpies can recognize themselves in a mirror. Crows, however, can recognize you. A recent study in the Seattle area has shown that crows can distinguish individual humans. They know if you’ve been naughty or nice, politely following people who fed them, and actively harassing people who treated them poorly, trapping them for study, for example. The birds need not have first-hand experience with the person recognized. They can be taught to recognize individuals by their parents or other crows in their flock. Similar behavior has been seen in gulls and other bird species. The study was reported in The New York Times.

Bad bird?

Tuesday, August 26th, 2008

If you looked at the cowbird video I wrote about a few days ago you saw the female cowbird pluck and toss to the ground an entire nestful of newly hatched warblers. The cowbird most likely then laid an egg in the nest. She was acting to help ensure that the female warbler would invest her entire energies in hatching the cowbird egg and raising the cowbird hatchling. Cowbirds have evolved to depend upon other bird species in this way. Most often, the cowbird simply lays an egg in the nest to be hatched along with the host-species eggs. Killing the young birds of the host species is an extreme in cowbird survival behavior. Is the cowbird a ‘bad’ bird for doing this? How did you feel when you watched the video? It was hard for me to accept without emotion that this is a natural behavior.

Hummingbird attack, myth info

Thursday, August 14th, 2008

attack-2837.jpgattack-2842.jpg For a superb and concise discussion of 10 hummingbird myths (misunderstandings), visit the Web site of Hilton Pond Center for Piedmont Natural History – This is always an interesting site, updated weekly. The photos here were taken recently near Lutsen, on the North Shore. An adult male Ruby-throated Hummingbird, defending his feeding territory, attacked a juvenile hummingbird of the same species. That bird was injured in the attack, and possibly died.