Winter is finally loosening its grip, and with the warm weather in the Brooks Range, the Colville River next to our home has started the first stages of breakup. The start of breakup for us is the flooding of the shallow parts of the river where the ice has frozen down to the river bottom during the winter. This “overflow” occurs as the water pressure from up-river continues to increase and the channel ice over the deeper parts of the river lifts up.
The ice needs to lift up between two and half and three feet before it will crack and let the water flow out over the frozen-down areas.
Start of breakup-first water
Clear brackish water boiling out of a blowhole.
Some of the shore leads created at this time can be over a half mile wide. Since the Colville has very little flow in the winter, the delta fills with brackish water from the Arctic Ocean during the winter months and the first water to flow up on the ice is clear greenish-blue color. It usually take from 1-2 days to flush the brackish water out of the delta after which the water becomes a dirty brown. Then it usually takes another week for the ice to weaken enough to break up and move out into the ocean.
Dark waters are shore leads, white channel ice over the deep water.
During the last wind storm, just before the river flooded, we had a special treat when a female Muskox and her calf showed up and spent four days in our local area. During the first two days they were here, it was storming so hard it was difficult to see them in the blowing snow. When they were lying down they were quickly covered with snow and blended in even more. When the storm broke, the cow and calf continued making their way to the west and were on an island west of us when the river flooded.
Upper photo shows female Muskox with snow packed in her pelt. Bottom photo was taken two days later, still whiteout but the wind has died down and they are enjoying a warmer day.
With our cold spring and heavy snow cover, the waterfowl were happy to see the river flood, and many White-fronted Geese and Brant were seen out bathing in flood water. Even with a few days of warm weather and melting during the day, the ground is nearly 95% snow covered, with only the higher polygon ridges and grass tussocks melted out.
The number of birds around our feeders at one time has started to decline, as birds pair up and move out onto their nesting territories. Our Lapland Longspur numbers peaked at around 150 during some of the worst parts of last week’s snow storm, and now we might see 15-20 at one time, with many birds shifting in and out of the feeders.
The Brant are our most numerous species now, with over 600 within sight of the house, either feeding along the river- banks or staking out nest sites in the nesting colonies. With this many Brant here already we should have an early hatch this year.
A pair of Brant
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