Mammals Archives - Page 22 of 36

February 22, 2016May 23, 2016

The Pygmy Rabbit: A ‘Cryptic’ Resident of the Sagebrush

Pygmy Rabbit, Brachylagus idahoesis — Pygmy Rabbit
Brachylagus idahoesis
Courtesy & Copyright 2007 Len Zeoli

Within the Intermountain West’s vast sagebrush ocean lives a tiny, furry creature that spends the majority of its time in or near a burrow of its own making. The Pygmy Rabbit, North America’s smallest member of the rabbit family, weighs about a pound and is about the size of a grapefruit.

The pint-sized mammal makes its home in sagebrush-studded areas in northern and western Utah, says Utah State University alum and National Park Service ecologist Tammy Wilson. Sagebrush provides food and cover for the rabbit and, in winter, provides 99 percent of its diet. The rabbit’s activity pattern is described as “crepuscular,” meaning that the animal is primarily active at dawn and dusk.

In addition to its petite size, the pygmy rabbit can be distinguished from cottontail rabbits and jackrabbits by its coloring and its ears. The pygmy lacks white fur on its tail; has smaller, very hairy, white-margined ears and a narrower face. Its fur ranges in color from salt and pepper gray on its back, to reddish-brown on its feet.

The Pygmy rabbit is a great example of ‘cryptic’ coloration; that is, a coloration that conceals or disguises the animal’s shape. The animal’s mottled coloring makes it virtually invisible in the shade of a sagebrush plant, which helps it to elude predators.

Pygmy rabbits produce up to three litters during a breeding season and the average litter size is six. The animals need to produce large families as they’re popular prey for a host of predators, including weasels, coyotes, badgers, bobcats, raptors, owls, badgers, foxes, along with rats, ravens and crows. Not surprisingly, the elusive animal is never far from the protection of thick brush and a maze-like network of tunnels.

Burrows

Known for their burrowing skills, Pygmy rabbits prefer loamy soils where they dig networks of tunnels with several entrances. In winter, the animals build tunnels in snow that connect to large cavities created by the weight of the snow on tall shrubs. The rabbits build the snow tunnels on top of the burrows they’ve dug in the ground.

“Everything the rabbit needs is inside,” Wilson says. “Their multi-chambered refuges provide food, protection from predators and protection from extreme cold.”

For example, on a zero-degree day in Utah’s northernmost Rich County, a pygmy rabbit in a snow tunnel enjoys a relatively balmy 32 degrees.

While ravenous predators are a hazard for pygmy rabbits, an even greater threat is shrinking habitat. As Utah’s sagelands give way to development, the tiny animal will have less food and less area for its cozy abode.

Thanks to USU’s Quinney College of Natural Resources for supporting research and development of this Wild About Utah topic.

Credits:
Images: Courtesy & Copyright 2007 Len Zeoli
Text: Mary-Ann Muffoletto, Utah State University College of Natural Resources
credit: Tammy Wilson, quantitative ecologist, National Park Service.

Additional Reading:

Pygmy Rabbits, Val Grant, https://wildaboututah.org/pygmy-rabbits/

Pygmy Rabbits, Nevada Fish & Wildlife Office, US FWS, https://www.fws.gov/nevada/nv_species/pygmy_rabbit.html

Brachylagus_idahoensis, pygmy rabbit, Animal Diversity Web, https://animaldiversity.org/accounts/Brachylagus_idahoensis/

Brachylagus idahoensis (Pygmy Rabbit), The IUCN Red List of Threatened Species, https://www.iucnredlist.org/details/2963/0

February 8, 2016June 30, 2020

Conservation: North and South

St George Winter Bird Festival, Courtesy St. George City — St. George Winter Bird Festival
Courtesy St. George City

I spent 2 gloriously warm days in Dixie where I attended the Winter Bird Festival, a grand event by any measure! I also had the good fortune of discovering “Citizens for Dixie’s Future” (henceforth CDF) which has taken on the onerous task of brokering piece between a surging population and the regions limited natural resources. Water topped the list, especially the Lake Powell Pipeline proposal. So I did a bit of reading from CDF’s well stocked library.

It soon became apparent that this multi-billion dollar project needs closer inspection on cost vs benefits. The costs must include not only dollars, but some unintended consequences such as continued urban sprawl in a super sensitive Mojave Desert ecosystem with an abundance of plant and animal life that I became more aware of through an excellent WBF presentation by naturalist educator Marshall Topham on the biodiversity of Washington County.

Located at the confluence of 3 major biomes- Great Basin Desert, Mojave desert, and the Colorado Plateau intersected by numerous rivers and the towering Pine Valley Mountains, Washington County is a wildlife mecca with over 350 species of birds listed, an excellent indicator of its natural wealth.

So my naturalist instincts and a propensity towards frugality led me to look for pipeline alternatives.

I found conservation to be the most obvious and least expensive alternative. In 2009, Washington County was at or near the top in the West for per capita water use at 294 gallons per day. In dramatic contrast Tucson was 161 and golf course and fountain studded Vegas at 222. If the county was to set a goal for 1% reduction in water use per annum, it would negate the need for the pipeline according to CDF.

We notherners in Cache County are being threatened with a similar situation. Our Bear River which supplies 60% of the surface flow into the Great Salt Lake and is the primary source for the Bear River Migratory Bird Refuge is under scrutiny for multibillion dollar reservoir development to serve the Wasatch Front. In addition to the hefty price tag, this has very serious implications for loss of prime agriculture land and high value wildlife habitat.

The following conservation practices are taken from the CDF.

• Providing rebates for efficient indoor water fixtures and outdoor landscape conversion
• Adding native, drought tolerant landscaping in new developments (and converting old)
• Implementing an increasing rate structure to signal conservation to the customer
• Conservation programs must include numeric targets and performance measures
• Updating building codes with more aggressive plumbing and appliance standards
• Increasing education and awareness about reducing peak water use.
• Implementing smart growth principals and preventing sprawl

An additional conservation possibility being explored by some USU folks is restoring healthy populations of beaver to the Bear River Watershed. This has potential for water storage rivaling planned reservoirs not to mention the supurb wildlife habitat created as a bonus. A question for the Dixie folks- how are the beaver populations in the Beaver Dam and Pine Valley mountains fairing?

This is Jack Greene for Wild About Utah.

Credits:
Image: Courtesy St George Bird Festival, St. George City and Citizens for Dixie’s Future
Text: Jack Greene, Bridgerland Audubon Society
Additional Reading:

Citizens for Dixie’s Future, https://citizensfordixie.org/

Big Bend Habitat Restoration Project: A Natural Work of Heart, Open Spaces-A Talk on the Wild Side, US FWS, https://www.fws.gov/news/blog/index.cfm/2016/3/25/Big-Bend-Habitat-Restoration-Project-A-Natural-Work-of-Heart [Accessed March 31, 2016]

September 21, 2015January 5, 2024

Yellow-Bellied Marmot

If you have explored the mountains of Utah, you’ve inevitably heard the iconic high-pitched chirp associated with Utah’s Yellow-Bellied Marmot.

Sporting chubby cheeks, large front teeth, a reddish-brown tail that spins like a helicopter rotor when fleeing, a greyish-brown back, white patch of fur between the eyes, and a yellow-orange belly, these sun-loving, flower-chewing mammals exude a Buddhist-type nature, especially when compared to their frantic neighbors, the pika.

Yellow-bellied marmots belong to the mammalian order Rodentia, in the squirrel family Scirudae. This family includes all species of prairie dog, chipmunk, and the woodchuck. Marmots fall under the genus “marmota.” The scientific name of yellow-bellied marmots is “Marmota flaviventris.” Although the origin of the term marmota is not certain, one accepted interpretation stems from a similar Latin word meaning “mountain mouse.” Flaviventris means “yellow belly” in Latin.

There are 15 species of marmot worldwide, all in the northern hemisphere. Most live in mountainous areas such as the Alpine marmot found only in Europe, though some live in rough grasslands. Although commonly believed to be in the same genus, the prairie dog is not classified in the genus Marmota, but in the related genus Cynomys.

When alarmed, yellow-bellied marmots emit a shrill whistle which earned them the nickname “whistle pigs,” by early settlers. Sometimes they make a “chucking” sound, which could explain another nickname, “rock chuck.” Additional monikers for marmots include “whistlers”, “mountain marmots”, and “snow pigs.”

Yellow-bellied marmots live at average elevations of 6,000-13,000 feet throughout western North America. They are often found in highland meadows and steppes, and almost always near rocks. Burrows are usually constructed in areas with plentiful plants which comprise the marmot’s main diet: herbaceous grasses and forbs, flowers, legumes, grains, fruits, and insects. Marmots spend the summer months sunning on warm rocks and fattening up in preparation for winter hibernation which can last up to 8 months.Thus, they are especially plump in the fall, right before hibernation, and reach weights of around 8-11 pounds. They may also estivate in June in response to dry conditions and a lack of green vegetation, only to reappear later in the summer when food is once again plentiful.

The typical social structure of yellow-bellied marmots includes a single male with a range of one up to four females. Males are territorial and aggressively protect their harem from other male marmots and smaller predators such as the ermine. Other predators to the yellow-bellied marmot include coyotes, foxes, badgers, bears, and eagles. Females raise their annual offspring of 3-8 jointly with other females within the harem. Baby marmots or pups are born relatively undeveloped and require large amounts of care until they emerge from the nest three weeks later. Only about half of marmot pups survive and become yearlings. If they make it through the first year, marmots may live up to 15 years of age.

Given that they spend about 80% of their life in a borrow, 60% of which is in hibernation, consider yourself lucky the next time you encounter a chubby, sun-bathing, whistling marmot!

For Utah State University Extension Sustainability, this is Roslynn Brain.

Credits:
Images: Courtesy and copyright Roslynn Brain McCann, Photographer
Text: Roslynn Brain McCann, Utah State University Extension Sustainability
Additional Reading:

Yellow-bellied Marmot, Species, Division of Wildlife Resources, Utah Department of Natural Resources, https://fieldguide.wildlife.utah.gov/?species=marmota%20flaviventris

Marmot Burrow, UCLA, Daniel Blumstein, https://www.marmotburrow.ucla.edu/watching.html

Marmot, Rocky Mountain National Park, https://www.nps.gov/romo/learn/nature/marmot.htm

Yellow-bellied Marmot (Rockchuck), Deseret News, 14 Mar, 1998,
https://www.deseretnews.com/article/629775/Yellow-bellied-Marmot-Rockchuck.html

August 31, 2015April 8, 2021

Ringtails

Ringtail (Bassariscus astutus), Photo Courtesy US FWS — Ringtail (Bassariscus astutus)
Photo Courtesy US FWS
San Andres NWR

I’ve long been intrigued by ringtail cats. I wasn’t quite sure where they fit in the grand scheme of things until I did some research while working in Zion N.P. where they were known to vandalize building contents and other mischievous behaviors.
These “mystery” cats are mostly nocturnal, highly secretive, very bright, and full of tricks and athletic feats that place them in an elite animal category. I was intent on seeing one but knew my chances were slight. On a midmorning hike into Hidden Canyon I was startled by something not far ahead of me scrambling up giant boulders. To my amazement, there they were- two ringtails hightailing in broad daylight- my first, and possibly last, sighting of these amazing animals!
The name “ringtail” comes from the seven or eight black rings on the animal’s tail. Although they are not related to cats, people have referred to them as miner’s cat, civet cat, and cacomistle (an Aztec Nahuatl term meaning half mountain lion). Along with raccoons and coatimundis, ringtails are members of the Procyonidae (raccoon) family. The scientific name, Bassariscus astusus, comes from bassar (fox), isc (little), and astut (cunning).

If one were to design an animal to climb along ledges and up vertical cliffs, the ringtail might be it. Their large tail provides balance for narrow ledges and limbs, even allowing them to reverse directions by doing a cartwheel. They can rotate their hind feet 180 degrees to quickly climb back down cliffs or trees as well as cacti. Furthermore, ringtails can ascend narrow passages by stemming (pressing all feet on one wall and their back against the other or pressing both right feet on one wall and both left feet on the other), and wider cracks or openings by ricocheting between the walls.

A ringtail’s total length ranges between inches with a tail length of 12 to 17 inches. They weigh two pounds or so. Vocalizations include squeaks, metallic chirps, whimpers, chitters, chucking, hisses, grunts, growls, and howls.
Like most omnivores, these hunters eat a wide variety of food. They have a seasonal diet, with plants and insects the favorite fall food, mammals and birds more common in winter, and insects dominate in summer. Preferred mammals include mice, woodrats, squirrels and rabbits. Ringtails also feed on nectar from agaves. Great horned owls are their major predator, along with coyotes, raccoons and bobcats.

Primarily nocturnal, ringtails don’t like daylight at a young age. Ringtails inhabit rough, rocky habitat, usually not too far from water, although they can subsist without free water if their diet consists of high protein prey or fruit and insects. In addition, they occur in semi-arid landscapes such as pinyon-juniper pygmy forests and oak woodlands. Ringtails den in tree hollows, rock crevices, other animals’ abandoned burrows or even abandoned buildings. Except in bad weather, they move frequently, rarely spending more than three straight nights in one den.

Mating occurs between February and May with one to four, hairless young born in May or June. Eyes open and fur covers their bodies by five to six weeks. They are weaned by fall and can mate near the end of their second year. Ringtails range across the southwestern USA and most of Mexico with outliers in northern California, Nebraska, Missouri and extreme southwest Wyoming.The genus Bassariscus consists of only one other species which lives in Central America. Because ringtails do not walk on the soles of their feet, unlike coatis or raccoons, they are sometimes placed in their own family, Bassariscidae. The ringtail became the State Mammal 1986.

For Wild About Utah, this is Jack Greene.

Credits:

Pictures: Courtesy US FWS, San Andres NWR
Text: Jack Greene, Bridgerland Audubon Society

Additional Reading:

Animal Fact Sheet: Ringtail, Arizona-Sonora Desert Museum, https://www.desertmuseum.org/kids/oz/long-fact-sheets/Ringtail.php

Ringtail (Bassariscus astutus), Wildscreen Arkive, https://www.arkive.org/ringtail/bassariscus-astutus/