Friday, August 19, 2016

Porcupine Caribou - Denali NP, Alaska

Caribou are a species of deer in North America that are known as reindeer in other parts of the world. In North America there are a number of subspecies. The Peary caribou, the smallest, are found in the High Arctic of Nunavut and the Northwest Territories of Canada. The boreal woodland caribou, the largest, range from the Northwest Territories to Labrador with a few individuals in northern Idaho, extreme northeastern Washington and small portions of British Columbia and Alberta. They are quite rare and listed as a threatened species. The barren-ground caribou, medium-sized, are found mainly in the Canadian territories of Nunavut and Northwest Territories and in Greenland. Finally, the porcupine caribou, also a medium-sized caribou, found in Alaska and western Yukon, are the type of caribou we saw in Denali NP in Alaska. Some lump the barren-ground and porcupine caribou into the same subspecies. 
These were the first caribou we saw, a mother and calf. The calf has spikes for horns and the mother's are not particularly large either, meaning she must be very young. We watched them for awhile as they ran along the hills near the side of the road. 
Other subspecies, generally known as reindeer in other parts of the world, include the: Novaya Zemlya reindeer in Russia; Finnish forest reindeer in northwest Russia and Finland; Kamchatka reindeer in Russia; Svalbard reindeer in Norway; mountain reindeer in Norway; and Siberian tundra reindeer in Russia. 
This fellow took my breath away. He was regal. The brow palm or shovel, the part of the antlers stretching out over the nose of the caribou, is found on the males, but not the females. 
We saw him a few miles before Kantishna, the end of the 92 mile road into Denali NP. That area of the park is where we saw the most caribou, and particularly the big males. 
Here the same male goes over a hill and disappears. The upper antlers that branch out are known as the top palm and the long branch that lifts them up is the main beam. 
One of the things that really sets caribou apart are their amazing antlers. Both males and females have them, but the males are larger and more extravagant. There are two separate groups of points, lower and upper, and lots of variation between subspecies. They shed and regrow their antlers each year, and each year they grow larger. The porcupine caribou antlers can stand higher than three feet. 
These two males were seen off in the distance, also near Kantishna.
This group of females and calves was way out in the tundra away from the road. We could hardly see them with our naked eye. This is a blown up photo from a 500 mm lense. We saw them on our journey back, about halfway along the road.
Male caribou are larger than female caribou, from 10% to 50%. In Denali, an adult will weigh anywhere from 130 to 350 pounds. Fur color varies among the subspecies, with the Peary being whiter, the woodland darker brown and the barren-ground and porcupine grayer. They have two layers of fur, a dense woolly undercoat and a longer-haired overcoat with hollow, air-filled hairs. This is their primary insulation. Their hooves are large and form a nearly circular print, acting like snowshoes. 
This big guy gave us our best look. He was not too far off the road and stayed put quite a while. Imagine holding up the weight of those antlers with a relatively small head. He was even closer to Kantishna, within a mile or two. 
He bends down to graze and gives a different angle to his antlers. 
Here he forages on some plants. His coat reminds me of a rock covered with lichen.
The porcupine caribou, also known as Grant's caribou and Alaska caribou, is named after the birthing grounds of a large portion of them, the Porcupine River, which is a tributary of the Yukon River. They participate in the longest land-migration of any land mammal on earth, going over 1,500 miles a year between their winter range and calving grounds. However, the Denali herd, which we saw, stays almost exclusively in Denali NP. The Denali herd is currently about 1,760 caribou, but it fluctuates greatly. It numbered about 20,000 in the 1920's and 1930's, then dropped to 10,000 from the 1940's through the 1960's. The numbers got as low as 1,000. Population decline was due to predation and some particularly severe winters. 
Here are some caribou antlers sticking up out of the tundra. I was the one who spotted these and asked the bus driver to stop. I was a pretty poor spotter otherwise. 
This female was the last caribou we saw on our way out, about 16 or 17 miles from the park entrance and not too far past where regular passenger cars are allowed to drive. I also spotted this one and got the bus driver to stop. 
I'm not sure exactly why, but I was quite taken by the caribou. I was about as excited to see them as any of the other animals we saw. 

2 comments:

  1. Their antlers are just so ginormous that it's hard not to be impressed by these animals. On some of them, the antlers seemed to be as tall as the animals carrying them. Beautiful, fairy tale animals.

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  2. Those first few pictures of the male are beautiful. What an impressive animal!

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