The peak of the breeding season for Striped Skunks is in March, which is why their tracks in the snow are fairly easy to come across, and why road-killed skunks are not an unusual sight at this time of year. Both males and females are actively seeking mates and travel as far as 2 ½ miles to scout out other skunks’ winter den sites.
A female is in estrus for a little over a week; only after mating does she ovulate, thereby increasing the chances of fertilization. After mating, the female skunk will aggressively attack any subsequent suitors, whereas the polygamous male will attempt to mate with all the females within his territory. (Photo: striped skunk den)
During these first days of April, Common Gartersnakes emerge from their hibernacula and often bask in the sun near the den where they spent the winter. (At this time they are more approachable than later in the season, should you desire a close look at one.) Males usually appear first; when the females appear, the males follow them in hot pursuit.
Common Gartersnakes are known for their impressive courtship ritual. Prior to copulation, as many as a hundred males will often writhe around a single female, forming a mass which is referred to as a “mating ball.” The male closest to the female rubs his chin on the head, back and sides of the female while aligning himself with her and eventually mating takes place. When it does, the other males that were in the mating ball leave and seek out other females. Female gartersnakes mate once; male may mate with several females. (Photo by Sally Fellows)
Eastern Chipmunks breed twice a year, in March and in June. If you’ve seen a chipmunk this spring, chances are it was a male, as males emerge several weeks before females. When they first come above ground, males check out female territories. When females appear they soon come into estrus, which lasts for roughly a week. However, they are only receptive to males for about a seven-hour period during this week. Outside of these seven hours, females will aggressively repel any advances. When males sense that their timing is right, they indicate their interest and intention by waving their tail up and down. This only occurs during the mating season – at all other times chipmunks only wave their tail horizontally back and forth!
A very high percentage (96%) of female Striped Skunks become pregnant each breeding season. Both males and females are covering a lot of ground this time of year (up to 2 ½ miles per night), visiting each other’s dens in search of a mate. While male skunks are promiscuous, mating with as many females in their territory as they can, females mate once and fight off any further attempts from other males.
Unlike primates, who experience “spontaneous ovulation” and ovulate midway through their menstrual cycle, female Striped Skunks, along with cats, ferrets, and rabbits, are what is known as “induced ovulators” – the act of copulation stimulates ovulation, which doesn’t occur until copulation has taken place.
You may have been hearing Coyotes howling more than usual lately. This is because their mating season has begun, and they are much more vocal prior to and during it. Another Coyote sign to be aware of this time of year is the abundance of Coyote scent-marking, with both urine and feces.
Female Coyotes come into heat, or estrus, only once a year for two to five days, in late January or February in the Northeast. It is not unusual to come across spots where both male and female Coyotes have scent-marked during this time. Often one will mark on top of or next to its mate’s marking. Sometimes the female’s blood can be seen in her urine, or, in the case of the pictured marking, her blood dripped onto the snow as she investigated her mate’s urine.
It’s that time of year again, when the odor associated with skunks wafts through the air, even though most skunks are denned up and in a state of torpor. This odor is the perfumed urine of Red Foxes, especially intense during their mating season, which begins around the middle of January. They use both urine and feces to communicate their presence, dominance and sexual status to other foxes and do so frequently (urinating up to 70 times per hour when scavenging at this time of year!). Stumps, logs and other raised surfaces often serve as scent posts.
According to scientist Dr. Mark Elbroch, Red Foxes “employ any of 12 different positions to urinate upon precarious perches…”. It’s fun to imagine exactly which one was used that allowed both a foot print and urine to appear on the pictured raised log!
All winter long, Eastern Chipmunks have been intermittently napping and running to their underground larder to snack every week or two. As spring approaches, the timing of their emergence above ground is affected by the weather, even though their tunnels are 18” – 36” below the surface. Within the last week chipmunks have been seen above ground. One would think they must be in a state of confusion, given the erratic weather we’ve experienced this spring.
Chipmunks waste no time once they are active. Most adult females are in breeding condition when they emerge (as opposed to males, which are in a state of constant readiness) and mate within a week. This involves 10-30 couplings within about a 6-7 hour receptive period. In a month or so, the results of these efforts will be born.
Bobcats are active at dawn and dusk, when their primary prey, rabbits and hares, are active. However, they are very secretive and you are more likely to come across their signs than bobcats themselves, especially at this time of year. January and February are the peak of Bobcat mating season, and females are busy rubbing their cheeks and bodies on scent posts, as well as marking their territory with urine. They also partake in yowling quite frequently, all of which enable male bobcats to readily locate females.
As a male approaches a female, he is either warmly welcomed or aggressively fought off, depending on her state of receptivity. Once she’s receptive, she becomes quite vocal, arches her back and circles around the male. Play-like behavior follows, with the pair throwing themselves at and chasing each other. Eventually mating takes place, lasting only about five minutes. Bobcats compensate for the brevity of their mating with the frequency with which they engage in it (up to 16 times a day for several days). When copulation ceases, males disappear and play no part in raising their young. (Source: Behavior of North American Mammals, by Elbroch and Rinehart) (Thanks to Roger Irwin, wildlife photographer, for the use of his photo. You may visit his gallery at www.rogerirwinphotos.com)
Under ice-covered ponds and lakes in dark, cold water, sometime between December and March, beavers mate. Latitude and climate affects the length of the breeding season, which is shorter and later in colder, more northern locations and longer and earlier in warmer, more southerly regions. February is the peak mating season for New England beavers.
Beavers are classified as monogamous, as once a bond has formed, they remain as a pair throughout their life until one of the pair dies, at which point a new mate is found. However, this does not mean they don’t stray. In a study of beaver colony genetics, researchers discovered that more than half of the litters had been sired by two or more males. So much for monogamy.
Although Snapping Turtles may mate any time between April and November, much breeding activity takes place during April and May. Snapping Turtle mating appears fairly aggressive, with the male chasing the female, grasping the posterior end of her carapace and then mounting her. He holds on to the edges of her shell with all four legs, often biting her head and neck while he inseminates her.
The female Snapping Turtle can keep sperm viable in her body for several months (and perhaps years). Thus, there can be multiple paternity in egg clutches and it may even be possible that a female’s eggs are fertilized in years when she does not mate. (Thanks to Jim Block for photo. To see a photo series of Snapping Turtles mating (and many other very fine nature photographs), go to http://www.jimblockphoto.com/2010/04/snapping-turtles/)
Red foxes communicate in a number of ways, one of which is to scent mark with urine. During their breeding season, which is at its peak this month, male fox urine takes on a strong skunk-like odor, detectable by most human noses. These “sign posts” advertise the fox’s presence, its dominance and sexual status to all other red foxes that pass by.
Foxes leave scent marks along the boundary of their territory, as well as within it. Often you will find both urine and scat placed strategically on elevated objects, such as rocks, stumps and vegetation emerging from snow as well as at the intersection of two trails. Both male and female foxes leave scent marks. Researchers have found that when foxes are looking for food, they mark up to 70 times an hour. When just traveling and not hunting, they do not mark as frequently.
Female Eastern Coyotes come into estrus only once a year, usually in late winter for two to five days. For two or three months prior to as well as during this time, males roam widely and scent marking by both males and females increases. During their mating season, coyotes often travel in pairs, and it is not unusual to find scent posts where both male and female have scent marked with their urine. (The female’s urine is often tinged with blood.) The percentage of females that breed in a given year (typically 60% to 90%) depends upon the availability of food and their physical condition.
Black Bear (Ursus americanus) breeding season begins in May and lasts until early July, with mating occurring mainly during June. The female traverses her territory at three times her normal rate during this time, laying down a scent trail which the male follows. Both male and female periodically intentionally deposit their scent by straddling vegetation, breaking off small limbs and biting, scratching and rubbing on trees (and telephone poles if available). Tree species often used for marking include White Birch, Balsam Fir, Striped Maple and Red Pine. When contact between the bears is eventually made, they nuzzle and chew on each other’s head and neck and may even wrestle a little. Mating occurs repeatedly for several days. (Thanks to Alfred Balch for photo op.)
Female Black Bears become sexually mature at three-and-a-half years of age. They breed in June and give birth in January or February (delayed implantation). Black Bears have a 2-year reproduction cycle: the cubs remain in the custody of their mother for roughly a year and a half, during which time the mother doesn’t mate. In May or June of the year following their birth, when they are 16 or 17 months old, the yearlings become independent and go off on their own — – just prior to black bear mating season. (Thanks to Jill and Bryan Marquard for photo op.)
After spending the winter hibernating in small streams and rivers, Wood Turtles awaken, become more active, mate (usually in shallow water), and eventually leave the water to begin foraging for food. Summer is spent mostly on land, traveling along streams — rarely do Wood Turtles stray farther than 1,000 feet from the water. In a few weeks, females will deposit between four and twelve eggs in a nest they dig in sandy soil.
Common Gartersnakes begin mating in the spring as soon as they emerge from brumation (a reptilian state of dormancy similar to hibernation in mammals, but involving different metabolic processes). The males leave the den first and wait for the females to exit. Once the females leave the den the males surround them, forming what is called a mating ball (one female and many males). The males give off pheromones that attract the female. After the female has chosen her mate and mated, she leaves. while the males stay to re-mate with other available females. The females have the ability to store the male’s sperm until it is needed and thus a female may not mate if she does not find a proper partner.
Great Blue Herons have returned to their nesting colonies in the Northeast and their breeding season is underway. These birds are monogamous for the duration of any given breeding season. A study found that most Great Blue Herons choose a new mate every year. After elaborate courtship displays have taken place, the pair copulates, frequently on the nest, and usually in the early morning or evening, as the female is away from the nest mid-day.
Eastern chipmunks typically emerge above ground in late March, at a time when most mature females are in breeding condition. It takes little time for nearby males to come courting. During their breeding period, females, for the most part, remain within their territory, whereas males explore within and outside of their territories in search of a receptive female.
Male suitors congregate on the site of a female in estrus and work out the hierarchy within the group. The top chipmunk wins the opportunity to breed with the female. During these dominance battles, the males vocalize, wave their upright tails from side to side, chase each other and fight. The dominant male then breeds with the female. She proceeds to mate anywhere from 10 to 30 times within about a six to seven-hour receptive period, not necessarily with the same male. All of this activity takes place within a week of when chipmunks come above ground, so keep your eyes peeled for those waving tails.
Reproductive activity begins when a beaver reaches the age of three years. Beavers mate in January and February, with the peak activity in mid-February. Typically mating takes place in the water (under the ice), but can occur inside their lodge. Kits, usually three or four, will be born in May or June. Beavers are monogamous and pair for life. (Note: ponds still frozen – photo not recent)
Coyotes mate in January and February, but pre-mating behavior started two to three months ago. During this period scent marking increases, as does howling, and males wander far and wide. Female coyotes come into heat only once a year. When this happens, and two coyotes pair up, they may howl in a duet before mating. If there is an ample food supply, most females will breed and between 60% and 90% of adult females will produce a litter. The size of the litter fluctuates with the size of the rodent population; lots of rodents means larger litters. The same pair of coyotes may mate from year to year, but not necessarily for life. (Photo taken at Squam Lakes Natural Science Center)
While the mating season, or rut, for moose peaks between late September and early October, mating behavior can already be observed. It is widely known that male, or bull, moose often paw a pit in the ground, urinate in it and then stomp in it in order to splash their underside, slap the urine with their antlers to disperse it, and lay down in the pit and wallow in their urine, soaking their undersides and neck. Their pungent urine serves as an aphrodisiac for female, or cow, moose, which are attracted to the pheromones it contains. A cow will enter a wallow, aggressively displacing the bull at times and even drink his urine.
However, it’s not just bull moose urine that attracts the opposite sex. The urine of a cow in heat (defined as the two days of their estrous cycle when they will allow a bull to mount them) is equally as attractive to bulls. At this time of their reproductive cycle cows frequently will urinate in the water and along the shoreline of lakes and ponds (look closely at photo).