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Wednesday, January 12, 2005

Today's little creatures at the feeder

The weather was nice today. It was sunny, and warm enough to start melting the snow. There were several different animals at the feeder today, including this pretty little fellow; a Male Western Rufous-sided Towhee:

They're really interesting birds to watch. They like to feed on the ground, and they kick up leaves and things with their feet. Just like chickens do. (Not for eating, Bingo!)

Here he is, making his calling sound. It's like a soft, "eeeeeeee" that ends with a question mark. Hard to explain, you'd have to hear it.

Here he is taking flight:

Of course Mr. Squirrel was there too. He's really enjoying the mixed seeds.

There has also been a male and female Varied Thrush eating here at the feeder. I would love to get a good photo of either of them, but they are very shy and elusive. I'll keep trying though, maybe I'll get lucky.


bingo and betty said...

1 can of chick peas, 1 tbs tahini-seasame base, 2-3 cloves garlic, 3tbs lemon juice, 1/3 cup olive oil, touch of salt-sea salt is best blend it all together (homus!)

Anonymous said...

I am curious about how far away you have to stand to take the pictures of the birds without scaring them away. I know that you are using a telephoto lens.

bingo and betty said...

Worms contaminated by radioactivity from the Chernobyl nuclear accident have started having sex with each other instead of on their own.

According to Ukrainian scientists, they may have changed their sexual behaviour to increase their chances of survival. It is one of the first pieces of direct evidence on how wildlife is affected by radioactive pollution.

Although there is a wealth of evidence on the impact of ionising radiation on humans, its effects on wildlife are poorly understood. In the past the International Commission on Radiological Protection, which recommends radiation safety limits, has set no limits to protect wildlife, assuming that as long as humans were protected, animals and plants would be too.

But in recent years the ICRP has abandoned this assumption and launched an investigation into how best to safeguard "non-human species". Many researchers are focusing on how wildlife has been affected by the radioactivity that spewed from the exploded reactor at Chernobyl in Ukraine in April 1986.

Remarkable changes
Gennady Polikarpov and Victoria Tsytsugina from the Institute of Biology of the Southern Seas in Sevastopol studied the reproduction of certain sedimentary worms that are vital to aquatic ecosystems. They compared the behaviour of three species in a lake near Chernobyl with the same species in a lake 20 kilometres away.

The lakes had similar temperatures and chemical composition, but the worms in the Chernobyl lake had received 20 times as much radiation as those in the other lake. The researchers found some remarkable changes in the worms' sexual habits.

Two species had switched from asexual to sexual reproduction, as they are capable of doing. The proportion of Nais pardalis seeking partners for sex was five per cent in the normal lake but 22 per cent in the Chernobyl lake, while the proportions of Nais pseudobtusa doing the same were 10 per cent and 23 per cent respectively. However, the third species, Dero obtusa, showed double the rate of asexual reproduction in the polluted lake.

Polikarpov thinks the worms have switched to sexual reproduction in an attempt to protect themselves from the radiation. Sexual reproduction allows natural selection to promote genes that offer better protection from radiation damage, and "the resistance of populations as a whole will be increased", he suggests.

Carmel Mothersill from the Dublin Institute of Technology, one of the experts helping the ICRP develop its new policy on protecting wildlife, agrees. "It is a plausible mechanism," she says.