As the moose rutting season comes to a close, signs of their breeding behavior are fewer and not as fresh. The pictured moose wallow, or rutting pit, was most likely created by a bull moose as a means of spreading his pheromones to receptive cows (although cow moose have been known to make them). After scraping the ground, the bull then urinates in the depression and stamps in it to splash the urine on his antlers (“antler perfuming”) and/or lies down in it, soaking the under side of his body, including the dewlap, or bell, that dangles beneath his neck. Every soaked surface serves to advertise his presence to cows in the area. Often the sound that the bull makes splashing the urine attracts cows, who run toward the bull and, by head bobbing and attempting to drink the urine (the sipping sound is attractive to both cows and bulls), encourage him to urinate more. (Thanks to Alfred Balch for photo op.)
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Abandoned bird nests are evident now that leaves have fallen off the trees. Consider the time and effort that goes into the construction of one of these single-use nurseries. Take the Red-eyed Vireo’s nest you see here lying on the forest floor. The female selects a nesting site — a time-consuming task, as the requirements are that it conceal the nest and provide shade for her young. (Too much sun will cause her to abandon the nest. One female who had selected a sunny spot was observed pulling nearby green foliage over her nest and fastening it in place with spider webs.) The female vireo then collects nesting material for the three layers of her nest: Exterior – tree bark, spider-egg cases, wasp-nest paper, lichen, green leaves and pine needles. (Nests exposed to sunlight may be decorated with light-colored tree bark such as birch bark.) Interior – bark strips and plant fibers. Inner lining – grasses, pine needles, plant fibers and animal hair. She then weaves these materials into a cup-shaped nest that is suspended from a forked branch by its rim. A trip for materials is made every 3 – 11 minutes and roughly twenty seconds is spent working each load into the nest structure. This intensive work takes the female vireo approximately five days – all accomplished without the aid of any hands or tools, and she only uses the result of all this work once. Fortunately, recyclers make good use of her efforts.
Pitcher plant leaves are primarily green in the summer, tinged with red, but as summer turns into fall, many become deep red. Although this red color was thought to attract insects, it appears that this is not the case. The color change, according to research cited in the Journal of Ecology, is due to the level of phosphorus this carnivorous plant has received from its insect meals. There is a limited amount of phosphorus in a bog and plants living there acquire it in different ways. The pitcher plant acquires phosphorus from insects that it traps. It then utilizes the phosphorus to revitalize the (green) chlorophyll in its leaves for photosynthesis. The deep red color that the leaves turn in the fall indicates that the plant has not had a good meal in quite some time.
Eastern Coyotes are heard with some regularity in New England, especially in the fall. The typical family unit consists of two parents and their young that have yet to disperse (often females). Together these four or five Coyotes serenade us with a very distinctive chorus, often several times a night. One wildlife biologist described this chorus as starting with a few falsetto yips, then blossoming into something resembling maniacal laughter, with the yips stringing together into chattering howls. Coyotes use their voices to communicate with members of their family, as well as with other Coyotes. If the family members have been off hunting by themselves, the howling serves to call the family back together again. The familial chorus also serves as a warning to other Coyotes not to trespass onto their territory. (Unless otherwise noted, my photographs are taken in the wild. This photograph was taken at Squam Lakes Science Center.)
Animals that remain active in New England throughout the year often make preparations for the colder months, when food is much scarcer. Eastern Chipmunks store up to half a bushel of nuts and seeds in their underground tunnels, Red Squirrels hang mushrooms and apples out to dry and White-footed and Deer Mice create larders, often out of abandoned bird nests. Once their young have fledged, most songbirds never re-use their nest. Mice find these empty cup-shaped containers perfect for storing seeds that they collect in the fall. The mouse that took over this Northern Cardinal nest (located in a rose bush) didn’t have to go far to collect a sizeable number of rose hips. One hopes that this isn’t this particular mouse’s only cached food, as most of the seeds (within the fleshy red covering) have been devoured. (Thanks to Marian Marrin for photo op.)
During their breeding season, or rut, bull moose display a number of behaviors that are not commonly seen any other time of year, and many of these behaviors leave obvious signs, including broken branches, scraped bark, wallows and tracks. Bulls roam their home ranges, thrashing their antlers back and forth against shrubbery and saplings while leaving their scent. The sound of their antlers beating against vegetation is thought to signal the bull’s dominance to other males, as well as serve to attract females. The pictured broken balsam fir sapling and its frayed bark are evidence of this behavior.