10.19.2015

What does marten scat look like?

We have partnered with Friends of the Central Cascades Wilderness in an effort to survey for the Sierra Nevada red fox on the Deschutes National Forest.

Guest post by Todd West, Friends of the Central Cascades Wilderness.

American martens (Martes americana) share habitat with montane red foxes (Vulpes vulpes cascadensis, V. v. necator) and coyotes (Canis latrans), and their scats are often encountered along trails when we look for fox sign.  As the smallest of these three carnivores, their scats are also the smallest, typically 1/4 of an inch in diameter or a little bigger (5-8mm) and two to four inches long (5-10 cm). Practice is needed to consistently distinguish them.  Often bent or curled up, marten scats are dark in color, often dark green, and commonly exhibit a plated look from curls of hair within the scat.  Over time, digested material will erode away from the scats, leaving bundles of curled hair.  Larger marten scats occasional exceed 3/8 of an inch diameter (10 mm) and five inches length (13 cm), approaching the size of red fox scats. However, they can be distinguished from fox scats by their twisty ends and tighter plating compared to the tubular look of fox scats.

Here are a few photos of individual marten scats which have been identify by DNA sequencing.






Hair bundles from several older marten scats appear in the photo below.  This sample was also mtDNA confirmed.


The remainder of the photos below are of scats which have been visually identified as marten but not mtDNA sequenced.  As above, a variety of size, shape, and dryness is shown.






When berries are available scats shift color and consistency.  This marten had apparently been consuming ripe huckleberries in the Mount Washington Wilderness.


It is common to encounter multiple scats near each other.  In this case an older marten scat appears at upper left with a fresher one at lower right.


As with other species, scats are typically left in the middle of the trail and less commonly along the sides.  If a trail has prominences, such as rocks or roots, in its tread martens may preferred these locations for scats.  The rock below provided a step in the middle of the trail with two fresher scats at left and an older, somewhat rain spread, scat at right.


Scat grouping also occurs across species.  In the below example the small, fresher marten scat just above the GPS was laid next to a coyote scat (also visually identified and not DNA tested).


Marten scats may be left repeatedly in some areas, increasing the size of the group.  The below image contains three or perhaps four scats of increasing age.  Larger groups often have additional smaller groups nearby, with occasionally as many as 7 to 15 scats within a 20 foot radius (6 m).




10.14.2015

Distinct population segments and the Endangered Species List

The distinct population segment (DPS) is conservation science jargon for a population that is unique and separate from the species as a whole. The term allows conservationists to propose putting part of a species on the Endangered Species List if the species as a whole is to not in danger of extinction. It is a way to preserve biodiversity within a species. The distinct population segment needs to be discrete and significant in order to merit inclusion on the Endangered Species List as an Endangered or Threatened Species. Individual critters or plants that make up a DPS  need to be some how biologically unique from the rest of the species to be considered as such, maybe bigger or smaller, or they may eat different prey, or mate at a different time of year, or have genes that are totally distinct from the rest of the species.

     Sierra Nevada red fox near Sonora Pass, CA (c) 2007 D. Baxter

Last Thursday, the Federal Government published what is called their 12-month findings - the decisions on whether to include a whole host of species on the Endangered Species List. When individuals or organizations think a species is in need of protection and inclusion on the list, they may submit a proposal outlining their reasons and the government has 12-months to respond, weighing the data and opinions presented to them. They must decide whether to list the species as in danger of extinct (Endangered), threatened with Endangerment (Threatened), or not in need of protection. Up for consideration was the Sierra Nevada red fox (Vulpes vulpes necator). This closest relative of the Cascade red fox inhabits the mountains of the Sierra Nevada and the Cascades in Oregon and California (Mount Lassen but not Mount Shasta). Based on what is known about this group of mountain foxes,  the Federal Government decided that this subspecies occurs as two DPS's (one if California and one in Oregon), that the California DPS warrants listing but the Oregon DPS does not because several recent detections have occurred in the state. Unfortunately the California DPS listing is Warranted But Precluded. More jargon, to mean that the populations in California are in desperate need of protection under the ESA, as they occur as two tiny populations of less than 45 individuals each, but the federal government is not willing to provide support to fund the steps necessary to bring the fox back from the brink.

This is all interesting news for one like myself who has a strong interest in the preservation of the Cascade red fox in Washington. From what the genetic and photographic data that I have collected on the Cascade red fox suggests, these critters occurs as several small populations in southern Washington and are very limited in distribution in the North Cascades. So the decisions made by the U.S. Fish and Wildlife Service vis a vis the Sierra Nevada red fox are telling for decisions made on behalf of the Cascade red fox. If I have learned anything from this ESA listing process, it is that data is power. Without explicit, compelling information, the government and perhaps the citizenry as well, are unlikely to react. It gives me motivation to continue the research we do on these little studied carnivores.