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Saturday, March 4, 2017

Methow Mammal Course - Class #3 Ungulates

Our 2017 "Conservation Course" started February 6th.  Below are notes taken by Avery Young.  See notes and videos from the previous classes here:
Class #1
Class #2
Learn more about the Mammal Course here

Class #3 - Ungulates with Sara Hansen & Jeff Heinlen, Feb 20 2017
plus a mini presentation by Mary Kiesau on Feb 27 (scroll down for that video and notes)

Watch and listen to the entire class on this video

This class focused on the Artiodactyla order (even-toed ungulates), and covered the two families Cervidae and Bovidae.  The wild animals in this order that are in Washington include:
Mule deer
Black-tailed deer
White-tailed deer
Columbian white-tailed deer
Bighorn sheep
Mountain goat

The Cervid Family
Mule Deer Herd by Mary Kiesau
Cervids are herbivores that lack incisors and walk on ungulated toes - meaning the weight is borne equally by the third and fourth toes, hence the name even-toes ungulates.  Okanogan County has an abundance of cervids - otherwise knowns as deer (and elk and moose)!  There are “odd-toed ungulates,” such as horses, who bear their weight primarily on their third toe. 
Cervids have an extraordinary sense of smell. Deer have 1000 scent receptors (and we have maybe 50) and their skulls have a huge nasal cavity to accommodate all those scent receptors. 

The main distinguishing factors for identifying cervids are their tail, metatarsal gland location, behavior, and sometimes antlers (although antlers are not as reliable).

Sexual dimorphism in deer is quite pronounced – males tend to be larger than females, and, except for the reindeer, only males possess antlers.  Our male deer species (including elk and moose) have antlers, which are temporary and regularly regrown unlike the permanent horns of bovids, from Spring through Fall.  Antlers are dropped shortly after the breeding season (the rut) is over, usually December into January.  In the spring when antlers regrow they have a velvet sheath and are some of the fastest growing tissue of any organism; they can grow an inch a day.

Phenotypically speaking, mule deer have a black tip at the end of their tail, and a white patch under their tails but their tails are usually not raised. Black-tailed deer have a thick, waterproof undercoat made with heavy oils which helps them deal with their habitat on the wet, Western slope of the Cascades (they are not found east of the cascades).  The bulk of the outward-facing part of their tail is black.  White-tailed deer, pervasive on the east coast of the US but also found here in Washington, have a broad, fluffy tail that is brown on the outer side and white on the underside.  When alarmed or running, their tail is often raised like a white flag. White-tailed deer have a much more aggressive temperament than other deer. Columbian white tailed deer, although rare, can be found in Southwestern WA; they are a protected species and not legal to hunt.
Mule Deer Fawn by Mary Kiesau

Deer breed late in the fall and have a 7-month gestation.  Females birth one or two fawns in late May to early June. The fawns stay with the does for about one year.  Females generally breed at 1.5 years, but can breed as fawns occasionally. Life span of deer is 8-15 years.

The WDFW Living with Deer website has a wealth of information!

One of the coolest things about Elk or wapiti (Cervus canadensis), aside from their size, is that they have “fangs.” Unlike deer and moose, elk still have a tooth on each side of their front upper jaw - what we call “canines.”  The teeth are ivory and are called “ivories.”  All the rest of their teeth are enamel.  There are only two animals indigenous to the Pacific Northwest with ivory teeth - elk and walrus.  An elk uses their ivory teeth to threaten and intimidate, snarling his upper lip to show his “fangs.”  A bull’s ivory tooth is much larger than a cow’s ivory tooth. 
Cow elks by Mary Kiesau

“Wapiti” is the name for Rocky Mountain elk in the Shawnee language and means “white rump.”  These cervids can live well into their 20’s (and there’s at least one in the Methow who probably has!).  Elk inhabit areas where there are a lot of open fields for grazing, and there are elk in certain parts of Okanogan county, though very few in the Methow.

Moose (Alces alces) are found in WA especially in the northeast part of the state. Moose means “twig eater” in Algonquin and they are the largest cervid in North America. They have an extensive range northward throughout Canada and Alaska. Moose endure an 8-month gestation, bearing 1-3 calves in June. Unlike most other deer and elk species, moose are solitary animals and do not form herds.  Recently 12 moose had to be moved out of downtown Spokane (this process involved a lot of drugs, sleds, and some strong people). 
Cow Moose by Mary Kiesau
Moose are starting to increase in numbers in the Methow too; Northcentral WA is kind of like the final frontier for moose in the United States.  Since 2010, there have been more and more incidences of road kill of moose. In talking to Native Americans, there are no stories about Moose in Washington. Why are they increasing here?  They need cold and they need mixed broadleaf and boreal forests with abundant shrubs for browsing.  Perhaps the increased amount of large wildfires over the last 20 years in WA has improved the  habitat for them.

Q: I have been feeding the deer at my house, what do you think of that?
A: It’s usually a bad idea. Deer have a 4-chambered stomach that has specific gut bacteria based on the vegetation and time of year. If you change that diet, their gut bacteria needs about 2 weeks to transition over to be able to digest the new food. This process takes a lot of energy. Sometimes deer stomach’s will bloat to the extent that the deer will actually die of starvation with a full stomach.

The Bovid Family
Bighorn Sheep (Ovis canadensis) are in the Bovidae family, along with mountain goats and other cloven-hoofed ruminants, including domestic cattle.  They are adapted for steep, rugged terrain. Males weigh up to 200 lbs and 8-10% of that weight is in the horns. It takes 7-8 years to get a full curl in the horns.  Ewes, the females, are smaller than the rams (can weigh up to 150 lb.) and have shorter, smaller horns that never exceed half a curl.  These cliff dwelling sheep live up to 10-12 years. The two digits of each hoof move independently. The posterior half of each hoof bears a rubbery pad for gripping. They use cliffs to escape predators such as coyotes, wolves, and cougars who have a very hard time scaling the cliffs.
Bighorn Sheep by David Moskowitz
Male bighorn sheep can be identified by the presence of large curled horns.  Horns are permanent and made of live bone - they don’t fall off like antlers but they will stop growing in winter and restart in spring which adds a ring in the horn. Counting rings in a horn makes it fairly easy to age a ram.  In the late fall rams start head butting to establish dominance over one another. You can sometimes see this spectacle exhibited South of Orville on Highway 9. Breeding occurs in late November through early December. Lambing occurs from late-April to mid-June on steep, rugged, natural habitats.

Bighorn sheep distribution in WA is in central and eastern Washington east of the Cascades. Local historic accounts go back to the late 1800’s, including in the Cascades just west of the Methow Valley.  By 1950, there were no more bighorn sheep left in Washington due to over-hunting and disease from domestic sheep, which had herds numbering in the thousands throughout Washington’s mountains.  The Washington Dept of Fish & Wildlife began reintroducing bighorn sheep from Canada about 60 years ago initially starting the Sinlahekin herd in northern Okanogan County.  Now, there are eight herds in Washington, including some that established themselves, with some population and genetic mixing between the herds and into Canada.
Bighorn Sheep Herd by David Moskowitz
What are the bighorn sheeps’ problems?  Cars are the cause of death for some sheep. Domestic sheep and goats can also pose problems because they can transmit a lethal strain of pneumonia to the sheep. Pneumonia can kill about 80-85% of a bighorn sheep herd. Dogs can sometimes be a threat to sheep. High barbed wire fences can also be a problem for these roaming ungulates when they get stuck in the fence. Psoroptic mange is a disease caused by mites which destroys the sheep’s hair, and is now rampant in the herds throughout Washington (in fact, Canada has even constructed fences to keep sheep with parasites from reaching non-infected sheep).

Bighorn sheep have not yet naturally recolonized in the Methow even though they used to be here.  They could probably survive here now, but they’d likely need to be reintroduced to get established. 

On Feb 27 Mary Kiesau gave a mini-presentation on Mountain Goats
 Watch and listen to that portion on this video

The mountain goat (Oreamnos americanus), which occurs only in northwestern North America, is the only genus and species of its kind in the world. The domestic goat is not closely related to the mountain goat.  They are native to the Cascade Range, and can be found from the Canadian border to the Oregon border. A few mountain goats inhabit the Blue Mountains of southeastern Washington where they have probably colonized from reintroductions in Oregon. Mountain goats are not native to the Olympic Peninsula; these goats descended from introductions from BC and Alaska in the 1920s.

Mountain goats are supremely adapted to the harsh conditions of the North Cascades.
Mtn Goat by David Moskowitz
They navigate high elevation cliffs and broken terrain very well with their split, flexible hooves.  Their compact bodies have strong muscular forequarters for scrambling, and thick hollow hair and wool "subfur" hold heat and repel wind and water (a wool coat that Native Americans harvested in the springtime to make yarn and blankets).  They are generalist herbivores who are said to eat “everything but rocks” - plants, including grasses and sedges, lichens, mosses, and conifers.

Both sexes look the same in general with all white coats and shiny black horns.  The male's horns have a wider base and curve back in a greater, more uniform arc. The female's horns tend to curve more toward the tip.  Probably the best way to distinguish male and female mountain goats is their urination posture. The male stretches forward with the front legs while keeping the hind legs stationary. The female stands in place and squats on her hind legs (kinda like a female dog).

The breeding season occurs from mid-November through early December. Females (or nannies) do not breed until at least 2.5 years of age. After a gestation period of 6 months, kids are born in late May or early June and closely follow their mothers for the first year.
Mtn Goats by David Moskowitz
Adult females (and their young kids) rank highest in the social order.  Yearlings drop to the bottom of the social order and are forced to forage last.  Kid and yearling survival may be less than 50 percent depending upon the severity of the winter. Causes of high mortality include avalanches, falls, predation (cougar, golden eagles), parasites, and poor winter conditions causing stress.  If a goat survives all this during its juvenile years, longevity is normally 10 to 13 years.

Mountain goats are considered mature at 2 1/2 years, but continue to grow through their fourth year achieving average weights of 125 to 155 pounds for females and 135 to 180 pounds for males.

Female and juvenile (nursery) groups range in size from two to many dozen, especially early in the summer when there's a lot to eat.  By the age of two, males or billies begin to disassociate themselves from nursery groups. Outside of the mating season, males tend to associate primarily with other males.

Mountain goat populations have declined overall in Washington from their historical levels that exceeded 10,000 animals as recently as 1961. As of 2008, the best estimate of the population is the 2,400 to 3,200 range.  Of these, about 450 live primarily within national parks. 

The dramatic drop in their numbers is being attributed to over-hunting from the 1950s to the late 1980s, when WDFW issued 300 to 400 permits a year to hunt goats on the assumption that they could be managed like deer.  But mountain goats reproduce at lower rates and their survival rates are lower than those of deer.

In the early 1990s, wildlife officials cut the number of hunting permits issued statewide to 15 to 20 annually (and raises $42,000 in fees to aid goat recovery).

Since 2002, researchers have tried to determine why the goat #s continue to decline in certain areas.  They learned that the main culprit is Interstate 90, which cuts across the Cascades.  And the issue is not being hit on the road!  The issue is that it’s a big road that mountain goats are reluctant to cross and therefore different goat herds are not mixing geographically and genetically.  After comparing DNA sequences on more than 200 Cascade goats, scientists found that genetic diversity of Cascade mountain goats is much lower than it is among significantly larger populations in British Columbia.  Inbreeding means a loss of genetic diversity that could affect the long-term survival of mountain goats in the Cascades.

The impact of such barriers are being studied nationwide. In Washington, concern about the effect of man-made barriers on mountain goats and other wildlife prompted the formation of the Washington Wildlife Habitat Connectivity Working Group.

Now, Washington is installing 14 wildlife crossings over and under Interstate 90 as it widens lanes east of Snoqualmie Pass. These crossings are designed to promote movement by many species, including goats.  (Hwy 2 is also a barrier but there are no plans there yet)

I think we’ll hear more about these wildlife crossings from Kris Ernest next week!

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