North American River Otters are not territorial in the classic sense of marking territorial boundaries. Instead they mark prime resource areas within their territory. Often, the site is near their den or a productive food area. They visit these sites repeatedly to urinate, defecate and roll around on the ground – so much so that the surrounding vegetation is often dead or dying and is referred to as a “brown-out.”
If an otter has been eating fish, its scat is often just a pile of fish scales. However, if it has been dining on crayfish and it is fresh, the scat can be tubular. No matter what form otter scat takes, a tell-tale sign (in addition to fish scales and/or crayfish exoskeletons) is the presence of clear, white or yellow mucus (scat-jellies). It is not always deposited, but occasionally you do find it. The origin of this mucus is not known – most likely it’s from the otter’s intestinal tract or its anal glands. Research shows that the presence of mucous deposits in some otter species indicates reduced prey availability or reproductive state. (Photo: Tubular otter scat is circled in red. Mucus is on right side of photo. Thanks to David Putnam and Natalie Starr for yesterday’s and today’s photo op.)
Reasons why Mystery Photo was not
Black Bear: Scat consists primarily of crayfish remains.
Beaver: Beavers defecate only in water, and individual pellets consist of tiny woody fragments resembling sawdust.
Raccoon: Raccoons have latrines where multiple scat is deposited, similar to otters. However, only otters deposit mucus.
Whose scat??? (Hint: Size – ¾” diameter; Location – near body of water) Please respond on Naturally Curious blog site, www.naturallycuriouswithmaryholland.wordpress.com under “Comments.”
Yesterday’s post about the Painted Lady butterfly has a mis-identified inset photo. Two butterflies in the genus Vanessa resemble each other closely – V. cardui (Painted Lady) and V. virginiensis (American Lady), both of which are found in the Northeast. While the main photo was correctly identified as a Painted Lady, the inset photo is an American Lady. Details enabling you to determine which of these migrating butterflies you are seeing can be found at http://bugguide.net/node/view/236368 . (Bugguide.net is an excellent resource for anyone wanting the identity of an insect or spider. You simply submit your photo and generous entomologists provide i.d.s). Many thanks to naturalist/author Kathie Fiveash for bringing this mis-identification to my attention.
If anyone reading this blog considers fungi too boring to be of interest, they may be about to experience a change of heart. A group of fungi known as “stinkhorns” generate a lot of interest, mostly because of their appearance and their odor. These fungi vary in color, shape and size, but they all share two characteristics. All stinkhorns begin fruiting by sprouting an “egg” from which they erupt, often as quickly as overnight, and a portion of their fruiting body is covered with slime (gleba) which contains spores.
Many species of Stinkhorns have a phallic form, including Ravel’s Stinkhorn (Phallus ravenelii). Brown, foul-smelling, spore-laden slime is located at the tip of this fungus. Attracted by the odor, insects (mostly flies) land and feed on the slime. With bellies full and feet covered with spores, the flies depart, serving as efficient spore dispersers.
For the past few weeks we have been witnessing the migration of thousands of southward-bound orange butterflies, a vast majority of which are not Monarchs (although they are having a good year, too) but Painted Ladies (Vanessa cardui). Both their large numbers and the length of time that they have lingered in the Northeast this fall are unusual.
This was a good year for Painted Ladies — they migrated north earlier than usual, arriving in mid-April, possibly giving them time to have an extra generation, reproducing twice instead of once during the summer. In addition, the unusual weather we’ve been having has not been great for migrating. The butterflies have spent a lot of time fueling up on nectar while waiting for a wind out of the Northeast to assist them in their flight to the Southwest. With the prevailing wind change we’re now experiencing, it’s likely many of them will resume their migration today.
The fruits of the Hophornbeam tree (Ostrya virginiana), also known as Ironwood for its strong, hard wood, are drooping clusters of papery, bladder-like sacs each containing a nutlet. The “hop” portion of its name refers to the resemblance of these fruits to those of true hops that are used in the production of beer. Hornbeam refers to a related European tree whose wood was used to yoke oxen; therefore, its American counterpart wood was also used as a “beam” with which to yoke “horned” beasts of burden.