Under natural and artificial conditions, Alpine marmots (Marmota marmota) are true hibernators with a single breeding season starting immediately upon emergence from hibernation. Over three mating and breeding seasons, hormonal and mating patterns of colony-housed reproductive female marmots were investigated after exit from hibernation. Blood samples were taken for progesterone, oestrogen and relaxin assays with parallel ultrasound investigations. Copulations were observed from the first day after exit from hibernation until the end of pregnancy and reached a maximum number on day 37 before parturition. Mating behaviour was observed between the dominant animals as well as between dominant and subdominant group members. In the first week after exit from hibernation, plasma progesterone was detected in half of the animals. During the third week, progesterone concentrations were significantly higher in pregnant than in non-pregnant animals or animals that had aborted. Immediately after emerging from hibernation, all successfully mated females showed higher serum relaxin values than non-successfully mated animals and this increase in relaxin concentration lasted until the end of pregnancy. The total concentration of oestrogen did not differ between pregnant and non-pregnant animals. The results of this study indicate that progesterone and relaxin might be useful indicators of early pregnancy in Alpine marmots.
When there are endless sights of picnic baskets, flip flops, and tanned legs, it's a perfect time to travel to a park or refuge to see the rut, or the bison mating season. The rut lasts each year from June to September, with most of the activity occurring between July and August. Breeding is strongly seasonal and very promiscuous. Bison are not monogamous, but rather polygynous, meaning bulls are will mate with more than one female, but females will only mate with one bull.
Beginning in early June as the breeding activities start, mature bulls will join mixed-sex groups to compete for mating opportunities. This is when the mood changes and the deep bellows of bull bison can be heard across the landscape. Bulls begin to court females through a variety of behaviors such as sniffing female genital areas and face-to-face lip curls. Wallowing behaviors also increase, where males will roll violently on the ground to display aggression. This wallowing behavior can cause so much dust to rise that the herds can disappear behind clouds of dust! A bull's tail also indicates mating status and behavior. A tail held high in a \"question mark\" fashion indicates a threat or challenge. This question mark signal is commonly seen as bulls lead a female away for mating.
The rut is an exciting time of year. Bellows fill the air, the group buzzes with activity, and male-male clashes can be seen. As the fall leaves begin to turn yellow and orange, the mating activities being to die down. But only 285 days later, reddish-orange baby calves are born, bringing excitement once again to the landscape.
Cat mating season is nearly year-round, with peak breeding occurring in early spring through summer. Indoor cats and those in warm climates are more likely to come into heat year-round. The mating season varies depending on the environment. It can be brought on by long hours of daylight, warm temperatures, and the presence of other cats.
While the tomcat is always ready for mating, the queen will only be available during her reproductive cycles. During the breeding season, most go into this heat cycle every three weeks, but each cat has her own pattern, which will usually repeat each spring or fall. An article in the Journal of the American Veterinary Medical Association found cats that were pregnant in all months of the year, but the percentage was highest in March, April, and May.
Animals are by nature seasonal creatures: Deer mate during the fall, so their fawns are born just in time for the spring season when food becomes more abundant. Polar bears look for mates during late spring and early summer and give birth to cubs between December and January.
This heat map created by Visme, based on the latest UN data on live births, reveals a surprising link not only between peak birth months and seasons, but also between peak birth months and latitude (which is the distance north or south of the equator, measured in degrees):
The findings of other studies have also been consistent with the insights gleaned from this heat map. For example, a comprehensive analysis of human birth seasonality published in the Proceedings of the Royal Society B concluded that peak birth months occur later in the year the farther south you travel, as clearly seen in the graph below.
What we can know for sure is that even though it appears humans may have a quasi-mating season, it is not really a true one as women are receptive to sex year-round and ovulate every 28 days, not annually. Unlike other animals, humans have concealed ovulation because they don't show any outward sign of biological fertility, which is still a mystery to scientists.
White-tailed deer become more active during mating season, also known as the fall rut. During this time of year deer are more apt to suddenly run onto roadways as bucks pursue does, risking the possibility of a collision with a vehicle. Increased deer activity is more likely to occur in the very early morning and around sunset when visibility can be difficult.
Warm spring weather means alligators are more active and more visible, the Florida Fish and Wildlife Conservation Commission said. Courtship begins in April then mating happens in May or June, according to FWC.
What Is Seasonality:Seasonal changes in temperature, rainfall, and day length all contribute to the cause of the breeding season in deer. In climates where seasonal changes are more extreme, seasonal changes in day length are the main cue used to time the breeding season (Lincoln). Puberty occurs at approximately 16 months of age and after this, they exhibit seasonal polyestrous. Deer respond best to short-day lighting, which means that they are not usually cycling during the summer months, but begin to show estrous behavior in late September and October (see diagram below) (Gordon).
The estrous cycle in deer varies from 17 - 22 days, depending on the species, and this cyclical breeding activity may continue for as long as six months in animals which do not become pregnant (Gordon). The seasonal changes in fertility are controlled by the secretion of LHRH (luteinizing hormone releasing hormone) from the hypothalamus, which is influenced by melatonin from the pineal gland. LHRH influences the secretion of LH and FSH from the anterior pituitary (Lincoln).
Seasonality in the Female:Female deer are short day breeders, so they generally come into estrus in the fall, from October to December (Dewey). This is triggered mainly by a decrease in photoperiod. A hormone called melatonin is produced by the pineal gland in response to the onset of darkness. When it reaches a certain level in the blood plasma it induces estrus (Webster). However, it is unclear how exactly this occurs. It is thought to be very similar to the pathway in sheep, but this has yet to be proven (Adam). In this pathway, there are high amounts of progesterone present in the deer during the anestrous season; this is true for both pregnant and non-pregnant individuals, though it is higher in pregnant ones (Plotka). The high amounts of progesterone cause estrogen to have negative feedback, limiting the amount of GnRH and subsequently LH, that are produced to levels that do not support estrus. The presence of enough melatonin in the blood plasma somehow triggers progesterone levels to decrease while increasing the responsiveness of estrogen receptors. When the progesterone reaches significantly low levels, estrogen begins having positive feedback effects on GnRH production, resulting in the first LH surge (Parrish). Deer generally cycle only a few times, until they are bred and become pregnant, when the increased progesterone again causes negative feedback of GnRH by estrogen. Deer can, however, continue cycling through March, if they fail to be bred (Webster).Seasonality of breeding is important in deer because it allows the offspring the maximum chance at survival since they are born in the spring to early summer when food is plentiful and it is not as coldout
Mule DeerMule deer are found throughout the entire western United States, including the four deserts of the American Southwest. These deer are also short day breeders and are polyestrous. The mating season for Mule Deer peaks in November and December. The Males will grow antlers prior to the breeding season and will often fight with other males for the right to mate with a female (Desert USA). Once the buck has found his doe, they will play chase games for several days before they will mate (Desert USA). They will then stay together for a few days after mating. Gestation is about 7 months in the mule deer. Females will give birth usually to a single fawn the first year she gives birth and will often produce twins in the following years (Desert USA).
Red DeerRed deer are most often found in western Europe, northwest Africa, Asia and northwestern America. Males and females will live separate from each other except during breeding season, which occurs in October. Females will give birth in late spring and will have from 1-3 fawns (Charlton). One distinction that separates them from other types of deer is, the males do not use their antlers to attract mates. The males will roar to attract the females (Charlton). The roaring will affect the outcome of male to male interactions and can even advance female ovulation (Charlton). Females can distinguish the differences between the roars and they will often choose a male that has a lower roar (McComb). It is thought that they do so since males with lower roars tend to have a larger body size, which is a sign of strength and good health. 59ce067264