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I know most creatures take time to learn some things.
Birds take some time to fly.
Human beings take some time walk or stand.
But in the case of the deer species, it's different. It can stand the same day it's born. Why is this so?
If you compare placental mammals in how much time they need to start walking, you'll see that deer are no exception. Humans are an exception.
Hypothesis of Obstetrical Dilemma
The hypothesis of Obstetrical Dilemma states that humans are born premature. We very much think this is because if we were to be born more developed (like other mammals), our big brain would not be able to make its way through the pelvis. Also, bipedalism leads to a narrower pelvis making the passage of the big brain even more problematic. For this reason, human babies are very dependent on the care of their parents for a long time. This hypothesis is called the Obstetrical dilemma (see Rosenberg 1992, Weiner et al. 2008 among many other papers as well as several books such as Ancient Bodies, Modern Lives for example).
Counter arguments to the Hypothesis of Obstetrical Dilemma
Note however that this hypothesis comes with a few potential contradictions, such as the fact that human gestation is no shorter than the gestation of humans' sister species. Indeed, in chimpanzees, for example, gestation lasts 243 days on average against 280 days on average for humans. These counter-arguments can be found in Dunsworth et al. 2012.
Thanks to @MattThrower and @AdamDavis for their helpful comments.
Despite this question having already two good and correct answers, I'd like to write this one just to explain the technical terms - describing what you're asking - mentioned by @jamesqf in his answer (last paragraph).
Mammal and bird (but also other groups) offspring can be classified as altricial or precocial. In a very simplified way:
- Altricial: A not very (to a certain degree) developed youngling, incapable of taking care of itself. Common examples among mammals are humans (see below), rats, cats, dogs and marsupials. Common examples among birds are the passerine, all of which are altricial.
- Precocial: Very (to a certain degree) developed youngling, active, mobile, capable of taking care of itself (mainly regarding locomotion: it doesn't mean the newborn is independent). Common examples among mammals are deer (as you said), horses, cattle, pigs, elephants etc. and, among birds, chickens.
Of course, this is a matter of evolutionary strategy, but it's interesting to understand some constraints. Cetaceans, for instance, have to be precocial, otherwise the newborn would drown.
Human classification is a little more complicated. Some authors classify humans as precocial (which is indeed our ancestral condition), like the other apes, because we have generally a single newborn which is born with the eyes open. However, due to the evolution of brain size in the human lineage, human babies are relatively less developed when compared to the other apes, which makes some sources classify humans as altricial.
Finally, you can find semi-precocial and semi-altricial as well, although those are less common terms in the literature. There is also superprecocial, as the birds from the Family Megapodiidae, in which some species are able to fly in the same day they hatch.
Deer are hardly unique in this, The young of horses, cows, and I suspect most grazing species are able to walk soon after birth. The reason, of course, is evolutionary: flight is the species mechanism for avoiding predators, so if they weren't able to flee, they would become lunch for some predator.
Other species have gone down an evolutionary route of having their young in some shelter - a nest or den, for instance - and having adults protect them while they're relatively helpless. (Marsupials take this to an extreme… ) Both strategies obviously work.
You can learn a lot more about this if you search for altricial and precocial species.
That you use the word "learn" in your question leads me to think that you're under a common misconception that people have about biology. It can seem self-evident to us that certain skills, for animals or humans, are necessarily "learned", but often, this isn't the case.
The first thing to note, there are a number of things that humans can learn, which they cannot naturally do, such as riding a bike, swimming, doing a cartwheel, speaking a second language, etc.
Second, we are most familiar with how humans grow from infancy to adulthood. We interpret infancy and early childhood as a period when a young person learns a number of basic physical skills, such as using their hands, walking, basic co-ordination such as running and catching, learning to speak, etc.
This leads people to assume that physical skills must necessarily be "learned", or practiced with increasing proficiency in order to attain a level of competence.
However certain observations of the natural world provide stark evidence that a number of physical skills, such as walking, swimming, even running and flying, need not necessarily be "learned", but can simply be grown, the same way that a limb or any other part of the body is grown. Yes, neurology and behavior can grow according to genetic pre-programming, just as the rest of the body does.
Consider the blue wildebeest: "calves can stand within an average of six minutes from birth and walk within thirty minutes; they can outrun a hyena within a day." On the plains of Africa, there are very few places to hide from predators. Clearly they are not learning, however, one may define learning, to run in a day.
Lest you think running is an easy skill to grow, and other skills are harder, megapodes birds are capable of flying the same day they hatch.
Once we understand that complex skills such as running and flight can grow, and need not necessarily be learned or practiced to competency by an organism, we then must question what exactly it is what we are witnessing when we see a young animal "learning" a basic motor skill. Is a young child who is learning to walk actually learning, or are we simply watching them grow the ability to walk, over a period of years, the same way their grow their teeth over a similar period? Or perhaps even a little of both, growth and learning?
The difference can be difficult to tease out in a scientific sense.
So let's look at human speech. Surely this is more complex than walking or flying? As adults, we struggle and take years to learn a second language. Children aren't completely fluent until about 5 years old.
But when we really take a look at language ability in children, we see that there is strong evidence that there is a fair amount of growth involved. A good summary of this can be found in Pinker's The Language Instinct:
Pinker attempts to trace the outlines of the language instinct by citing his own studies of language acquisition in children, and the works of many other linguists and psychologists in multiple fields, as well as numerous examples from popular culture. He notes, for instance, that specific types of brain damage cause specific impairments of language such as Broca's aphasia or Wernicke's aphasia, that specific types of grammatical construction are especially hard to understand, and that there seems to be a critical period in childhood for language development just as there is a critical period for vision development in cats. Much of the book refers to Chomsky's concept of a universal grammar, a meta-grammar into which all human languages fit. Pinker explains that a universal grammar represents specific structures in the human brain that recognize the general rules of other humans' speech, such as whether the local language places adjectives before or after nouns, and begin a specialized and very rapid learning process not explainable as reasoning from first principles or pure logic. This learning machinery exists only during a specific critical period of childhood and is then disassembled for thrift, freeing resources in an energy-hungry brain.
So the idea that complex skills, even language, must be learned, is one that should be looked at critically. Considering the evidence that flight and walking can be grown, the next question is how much learning organisms actually do.
On a practical note not previously mentioned: If deer couldn't walk very soon after birth, they would be very vulnerable to predators, as would their parents who would have to remain nearby to take care of them. This is true for many creatures - even for predators themselves, if you think about it.
Males will spar with each other during the rutting season, usually in the summer months. They will use their antlers to test each other's strength, fighting for dominance of the herd and, thus, mating rights over the females. They lose the antler after each rutting season, growing a new pair each year.
The dominant male will continually search, often going without food for days at a time, among the females for those that are in season and ready to mate, as females only achieve this state for between two and three days.
The California Mule deer and Black-Tailed Deer are closely related deer whose range covers much of the state of California.
With rapid development of rural areas, deer are losing their natural habitats and are forced farther into suburbia. They now live close to our homes and towns. In a world where contact with wildlife is more frequent, we may need to change some of our behavior to find ways to live with them. To coexist with deer, they must be understood.
Spring and summer is the time of year deer give birth to their young. A deer may have between one and three babies, two being most common. Fawns are born from April though June. They are born with their eyes open and fully furred. The fawn is able to stand in 10 minutes and can walk in 7 hours. Young fawn stay with their mother through next winter.
Healthy baby fawns are daily left alone by their mothers while the mothers forage for food. Unfortunately, many times a lone fawn is picked up by people who mistakenly think the fawn has been abandoned. The fawn is then brought to Native Animal Rescue by the “well meaning” people for rehabilitation. Sadly those fawn have been taken from the mother unnecessarily. In other words, they were kidnapped.
Kidnapped fawns should be immediately returned to the exact location where they were found and the left alone. The mother will return and always take her baby back. If however you do not leave the fawn alone, the doe will not return to her baby as she will sense danger. Once she senses the potential danger is gone, she will then rejoin her young.
Remember, if you encounter a fawn lying quietly in the woods, do not disturb. Mom is nearby and will go back to her baby when you are gone.
The only time a fawn should be picked up and brought to NAR is if it is obviously ill or injured.
If a fawn is wandering aimlessly and crying, that may be an indication the mother may have been hurt and will not return. Call Native Animal Rescue for advice.
The fawnʼs natural predators are cougars, coyotes, bobcat and domestic dog packs. It is of vital importance that we keep our dogs contained to prevent needless dog attacks on fawn as well as other wild animals. Too often Native Animal Rescue receives injured deer due to attacks by dogs. Most of those injured deer do not survive. There is a leash law in Santa Cruz County so it is of the upmost importance to abide by the law and keep dogs confined to their own territory. Doing so will help prevent attacks on our defenseless native wildlife.
Fawns are born scent-free and have white camouflage spots which protect them from predators. The doe continues to keep her babies scent free by consuming her fawns urine and droppings. This is yet another reason why humans should never touch a fawn. Leaving human scent on their body will attract predators to the fawn. If you have touched a fawn and are returning the fawn to the place where found, please do the following:
- Put on rubber gloves and get a towel.
- Rub the towel in the grass then wipe the fawnʼs body with that towel to remove human scent.
- Leaving the gloves on, return the fawn to the place where found. Now the fawn is once again scent-free and waiting for mom to return.
The destruction of habitat through logging and development has played a large part in the decrease of deer. Sadly, automobiles destroy thousands of deer annually. The following are a few tips on how to make your drive safer for you and the deer:
- Heed wildlife warning signs and adhere to the speed limit.
- Where forest or fields are on both sides of the road, scan for wildlife at all times. Be particularly attentive during dawn, dusk, and nighttime hours.
- At night, always watch for reflection from the eyes of deer and other nocturnal animals.
- If a deer “freezes” in your head lights, stop if safe and turn your headlights off and on so the animal can pass.
- When you see brake lights, it could mean the driver ahead of you has spotted deer. Stay alert!
- If one animal crossed the road ahead of you, stop and watch there will probably be others.
- Deer hooves slip on pavement. A deer may fall in front of your vehicle just when you think it’s jumping away.
- If you accidently hit and kill a deer, move it far off the road. Often a doe will be killed and her fawn is still there in harms way. The living fawn/s will stay by their dead mom and/or dead sibling for hours.
- If an adult deer is hit by a vehicle and wounded, immediately call Santa Cruz County Animal Services (831-454-7200) or the non-emergency number of the local police for assistance. Please do not let the deer suffer.
- Do not touch an injured deer as their sharp hooves will do major damage to you.
Deer of are such beautiful creatures to observe, but if you do not want them in your garden, here are some helpful hints to humanely keep them away:
- Fruit trees are a natural attractant. Fruit should be harvested and fallen fruit removed.
- Grass and underbrush should be kept trimmed.
- Attractants can be surrounded by repellant plants such as: catnip, chives, garlic, lavender, onion, sage, spearmint and thyme.
- Visual stimuli like strobe lights, mylar tape, scarecrows, bright lights, motion activated water sprays, loud noises and radios will help keep the deer away.
- Deer fencing at least 8 feet high or simply fencing individual plants.
If you see an adult deer with a broken leg or other injury, leave the animal alone unless it can’t stand up. Even though the injury may take a long time to heal, this is far preferable to the trauma of chase and capture. Wild animalʼs ability to heal and their adaptability of some injuries are quite amazing.
Being able to observe deer and enjoy their incredible beauty, innocence and wildness is an unforgettable experience and privilege that we can all enjoy.
For more information on deer or any other wild animal, please call Native Animal Rescue at: 831-462-0720 and visit our website: www.nativeanimalrescue.org.
Native Animal Rescue
Wildlife Rehabilitator/Board Member
Fawn (Baby Deer) Information and Photos
White-tailed deer mate in the fall from October to early December. Their babies, called fawns, are born approximately seven months later in the early spring or summer. White-tailed deer are considered a uniparental speciesmeaning the fawns are only cared for by one parent (the doe). Shortly before the doe is ready to give birth she chooses a birthing area, a spot covered by vegetation that will help conceal her fawns from predators. Once there, she will drive off any other deer that try to enter the area, even her own offspring. Her existing female offspring may rejoin her and her newborns later on, but the males will either leave voluntarily or be permanently driven off to start life on their own.
Fawns weigh about 8 pounds at birth and twins are quite common, especially if the doe has been healthy and well-fed throughout her pregnancy. They are helpless at birth, but able to stand and take a few steps within the first hour. Because the blood and fluids at the birthing site may attract predators, as soon as they get to their feet the doe leads the fawn to a new sheltered spot called a form. If she has twins, the doe may place each fawn in a separate form up to 200 feet apart so that if one is discovered by a predator, the second will remain safe. At birth, the fawns reddish-brown coats are dappled with white spots. This makes them nearly invisible to predators while lying motionless among vegetation.
The Fawn's First Year
The fawns will spend their first three to four weeks in the form, or until their wobbly legs grow strong enough to keep up with their mothers. The does dont tend to their fawns nonstop since her fawns are born odor-free, the doe keeps her distance, except when nursing, to avoid having her own scent draw predators to them. The fawns are born with the instinct to remain still and quiet while their mothers are away. Its common for people to happen upon newborn fawns curled up in a field or forest alone and mistakenly assume they have been orphaned, but that is almost never the case! If this happens to you, enjoy the moment and then quietly move on. Although the fawns mother is probably not visible, it is likely that she is somewhere nearby.
After about three weeks of hiding, the fawns can run fast enough to keep up with their mothers and start following them everywhere. The protective does begin to show their young how to find food, but even after the young start grazing or browsing, they will continue to nurse for some time. Eventually they will rely solely on the foods they will eat as adults: acorns, corn, soybeans, mushrooms, grasses, tree leaves, buds, twigs and bark, wild grapes, apples and assorted shrubs.
Navigating Life on Their Own
White-tailed deer are considered fawns until they are a year old, when they are called yearlings. The death rate among both fawns and yearlings is high. They are killed by predators (wolves, coyotes, bears, and bobcats) bad weather, disease, or a lack of maternal care if their mother is killed or abandons them. Researchers have estimated that as many as 30% to 40% of white-tailed deer die during their first or second year.
After they reach their second year the females are called does and the males are called bucks or stags. Female whitetails will remain with their mother until they are about two years old. Males leave their mothers after the first year. Distinguishing between the male and female genders becomes easier as they grow. Females tend to have a slighter frame and do not have antlers. Males are larger and begin growing antlers several months after birth. They shed their antlers in the winter every year, and start growing a new pair each spring. The age of a deer cannot be accurately determined by the size or number of points (tines) on an antler. Antler development is determined by nutrition, not age, although older more experienced bucks do tend to grow the largest racks.
Birth Cycles for Deer Species
Different deer live in different regions. Knowing which species is in yoru area is important to know when deer give birth.
White Tailed Deer will be familiar to everyone in North America and around the world. They’re one of the most widespread deer in the world. After-all, Bambi is a whitetail deer in the classic Disney movie.
Females are ready to mate in November, although the mating season including the rut is from October to December. Following a gestation period of 200 days, the doe will birth to between one and three fawns during April, May, or June of the following year.
Mule Deer follow a slightly different mating ritual to other species because the male and female spend an extended amount of time together before and after breeding. This may be several days on either side, where the two will engage in chase rituals.
Following peak mating season in November and December, pregnant females carry their fawn for around 7 months. Mule deer give birth during the early summer. First-time mule deer mothers birth a single fawn but will often produce twins in following years.
Another hugely common species, the Red Deer (known as the Elk or Wapiti in North America) are found in Europe, Africa, Asia, and parts of the Americas. They face different seasonal changes.
Red deer are unique because males do not engage in antler combat with each other and instead use low roars to compete for females.
Following a late autumn breeding cycle, female red deer give birth to between one and three fawns during late spring (May and June) the following year.
In terms of breeding, these animals face some specific challenges because of their location in the Arctic. Polar regions present different seasonal changes, which is why reindeer typically enter the mating season as early as late August while it is still summer.
That said, September is the usual start of breeding, which lasts for 4 weeks. Following a seven month gestation period, reindeer doe will give birth to fawns from early April to June.
Like Reindeer, the European Roe Deer have a slightly adjusted mating season. They start mating in mid-August, which is the height of summer in their European ranges.
That said, this species has a unique physiology. The female ovum or egg won’t fertilize until months after mating, usually between October and early January. This way they avoid winter births.
Roe deer give birth during May and June, with 1-3 fawns born to each pregnant female.
Fallow deer are widespread across the United States, Europe, and Asia. Mating season for fallow deer lasts from September to November. Breeding typically occurs during October.
Female fallow deer have a gestation period of seven and a half months. Fawning season for this species starts in late May, though fawns may be born through June. Fallow deer usually give birth to a single fawn, but twins are not uncommon.
Day One - The Birth of a Fawn
Spring has arrived and there is new life in the forest. Abundant rains and warm temperatures have transformed the starkness of winter into a lush green landscape. Almost overnight, the new growth of spring forbs, grasses, and vines provides an abundance of succulent deer forage. It’s a time of plenty for the deer and a chance for them to restore body condition that has declined during the bleak winter months.
The changing seasons and the abundant regrowth has also set the stage for a miracle that will be repeated millions of times over the next few months. Following the frenzy of the rut last fall, does have been carrying this year’s fawn crop. Now, seven months later, it’s time for new life to enter the deer woods.
In response to increasing daylength and the hormonal changes during late pregnancy, a doe’s behavior changes dramatically. Although does are normally tolerant of other deer, particularly during winter, a few days before giving birth she becomes increasingly intolerant of other deer, including her own young from last year. A few days before giving birth, she isolates herself in a small ‘fawning territory’ and drives away all other deer that intrude. At this time of year, it is not uncommon to see yearling bucks and does wandering around alone, or with other yearlings who likewise have been driven away by their mother. For young males, this separation may be permanent, but yearling does likely will rejoin their mothers later in the summer.
An experienced mother typically returns to the same fawning territory that she used in previous years. Research by John Ozoga in Michigan found that mature, dominant does always selected the best fawning sites, and that her daughters from previous years often established fawning territories in adjacent areas. This isolation of the mother and newborn is essential to establishing a maternal bond during the critical imprinting period. Although it appears that a doe will imprint on her fawn after only a few hours, it may take several days for a fawn to become fully imprinted on its mother.
Late-term does appear to be noticeably uncomfortable. About 1 to 2 weeks before birth the udder begins to swell. In our research facility, we have noticed that within a day or two before giving birth does often start pacing and the tail may be held at ‘half-mast’. However, this may be due to the close confinement of other deer and may or may not happen in the wild.
Following a series of contractions, fawns are born feet first with the head tucked between the forelegs. Usually, the doe is lying during the process, but it is not infrequent for a fawn to be ‘dropped’ by a standing doe. The birthing process proceeds quickly. It may take less that 30 minutes from the time the doe lies down until the fawn is born and completely cleaned, although there certainly is a lot of variation among does. A young doe’s first labor is usually more difficult and prolonged than subsequent deliveries. If the doe is carrying twins, the second fawn is born 15 to 30 minutes after the first.
Fawns typically weigh between 5 and 8 pounds. Single fawns generally weigh more than those born as twins, and male fawns almost always outweigh females.
The newborn fawn is covered with amniotic fluid and other membranes, which the doe begins cleaning immediately. Her licking of the fawn can be quite vigorous and her intense maternal attention may even knock the fawn down as it attempts to stand. In a short time, the fawn is clean. Does will consume all traces of these membranes along with the afterbirth. In fact, her cleaning is so thorough that she will often eat bloodstained leaves at the birth site. The primary purpose of this process likely is to help the mother identify the scent of her fawn and to imprint on the fawn. However, this thorough cleaning also helps to minimize odors at the birth site that may be attractive to predators and a host of insects. Consumption of the afterbirth also might help supply the doe with a variety of nutrients during this energy demanding period.
Fawns begin nursing almost immediately. This first nursing bout provides the fawn with a high-protein milk called colostrum. This colostrum is essential to the fawn because it provides the fawn with a variety of antibodies that help it resist disease until it’s own immune system is fully functional.
Fawns are able to stand within about 10 to 20 minutes after birth, but their weak, wobbly legs won’t carry them far. Often the exhausted doe is content to lie still for a few hours after birth and allow the fawns to gather strength and coordination before moving them away from the birth site. Although twins are born at the same site, they are separated after birth and are kept at different bedding sites for their first 3 or more weeks of life.
Very young fawns do not appear to have any natural fear of predators, and may even walk up to humans. If this happens to you, resist the urge to touch or ‘rescue’ the fawn. Rather, just leave it alone - you can be certain that mother is not far away and will be back to care for the fawn as soon as you leave.
Waiting for Warmth
Garter snakes come out of their dens in the spring when the temperature starts to increase. Click to enlarge.
Animals that hibernate underground through the winter and breed during the spring cannot track the length of daylight to figure out when to reproduce. Garter snakes have solved this problem.
They use the changes in temperature between seasons to time their hibernation and reproduction. When daytime temperatures drop to 0°C (32 °F), these snakes slither into their underground dens to wait out the cold. As air temperatures gradually warm to 20-28°C (68– 82°F), garter snakes awaken. They emerge from their dens to court and reproduce.
20 Things to Know About Deer Body Language and Behavior
A whitetail's anatomy, biology and behavior directly influences its non-verbal communication. Here's how.
1 | Striking
This fawn is learning herd-hierarchy lessons, one swat at a time. The dominant deer raises its front foot and attempts to put it down on the other’s neck or back.
2 | The Ear Drop
The ears are held outward from the body. It’s the lowest form of threat as illustrated here between a mature buck and a young one. The ear position and a stern look conveys status. It is used frequently and by all deer in all seasons.
3 | Alert
Busted! Every deer hunter who has been identified as the boogeyman by a deer knows this look. Alert ears forward are listening intently and facing the perceived threat. The nose is testing the limits of your scent-control system and the eyes are laser focused for the slightest unnatural movement. Be still and pray for a shot opportunity if the animal doesn’t bolt.
4 | Tail Half-Lifted
Deer live in groups and within each is a dominant deer. Every other deer has a place in the hierarchy. This buck is dominant within an early fall bachelor group. Note this behavior when pre-season scouting to learn which bucks may dominate the area during the rut.
5 | The Radar Sweep
Deer rotate their ears listening in front and behind simultaneously, especially when bedded. Silence your movements and gear as much as possible — even when deer are looking away from your position. Use windy days to beat a deer’s ears when stalking or still hunting.
6 | A Hard Look
During the rut, a buck lowers its head, lays back its ears, raises its hair and stares at the offending deer for several seconds. Deer usually avoid eye contact so this is a threatening display and may precede an antler rush during the rut. Be ready if you see a buck in this posture. Another buck is nearby.
7 | Sidling
Rival bucks slowly approach and circle each other with heads held up, ears back, hair erect and their bodies at about 30-degree angles from each other. If one retreats, as in this photo, a confrontation is avoided. However, sidling usually precedes flailing or an antler rush.
8 | Tail and Rump Flare
This indicates a high degree of alarm. This buck is signaling to other deer in the area that danger is near as a pair of coyotes passes by. Follow the deer’s line of sight to identify the source of it’s alarm. Be ready. The deer may be mere seconds away from bolting.
9 | Tail Flat
If hiding or greatly alarmed to danger at close range, a deer will press the tail flat so only the brown hairs are visible. It’s also used when danger is at a long distance and there’s an opportunity to escape undetected. Note a fleeing deer’s tail position. Mature bucks sometimes keep their tail flat when vacating an area, drawing less attention.
10 | Tail Flagging
This usually signals the end of a hunt as deer run from perceived danger. The highly visible white tail is held upright and waved freely from side to side, exposing the white underside and rump patch. Tail flagging helps keep a group of deer together, especially in heavy brush or thickets.
11 | Tail Swishing
The all-clear signal is a casual, side-to-side tail wag that shows the deer has decided everything is okay. It tells other deer in the area that a threat has passed and they can come out of hiding. To avoid being detected, when hunting, hold up making movements when a feeding deer swishes its tail. It often will then raise its head to scan for danger.
12 | The Foot Stomp
The dreaded foot stomp is used when a deer senses danger, but can’t identify the object of its suspicion, like a hunter for instance. A forefoot is lifted slowly, held for a second, and then stomped forcefully downward releasing scent from the interdigital gland. This may be done repeatedly while the deer uses its eyes, ears and nose to identify the source of alarm. It tells other deer that potential danger is nearby. The vibrations can be felt over a long distance. The sound is heard over short distances. Be still. If the deer doesn’t snort and bolt, consider sitting tight, especially during the rut when deer are on the move throughout daylight hours.
13 | Tending Foot Stomp
As a doe is coming into estrus, but not yet ready to breed, she often heads to thick cover to escape a buck’s advances. This foot stomp occurs when an agitated, impatient buck stomps then rushes the doe in an effort to push her from cover. Bucks will sometimes snort wheeze at the doe, too, showing their agitation. Be ready for the pair to break cover and the chase to resume.
14 | Flailing
Deer rise up on their hind legs and strike at each other with front feet, similar to boxing. Contact is rare. But it can certainly happen.
15 | Flehman or Lip Curl
Lip curling occurs when a buck finds a place where a doe has urinated. The buck sniffs the spot then extends his neck and chin to about a 45-degree angle and curls back its upper lip and nostrils for several seconds. This action exposes the vomeronasal organ located in the roof of the mouth that helps elevate a buck to peak testosterone levels.
16 | Antler Threat
One buck lowers its head and points its antlers directly toward its rival. This signals the intent to charge. If the opponent responds with an antler threat, sparring or antler rush ensues. Two mature bucks battling for breeding rights can be one of nature’s most dramatic displays. Make your move while the bucks are engaged.
17 | Buck Run
The buck pictured, with neck extended and head low, is closely following a doe. He makes long, low tending grunts, blows and wheezes during the chase. Bucks chasing does often have a low profile. Be observant and don’t expect to see them in a more visible bounding gait.
18 | Blowing or Snorting
Deer alert other deer to danger over a wide area. When blowing, deer forcibly exhale air through the nostrils repeatedly in drawn out “whooshes.” As the deer turns to bound away, it makes single, very short but explosive snorts. Both are a kick in the gut when hunting. Make sure the blows and snorts are directed at you before abandoning the hunt, though. If you feel the deer couldn’t have detected you, give it some time. Watch for predators or other hunters that may have been the source of the blowing before moving.
19 | Grunt-Snort-Wheeze
The grunt-snort wheeze happens quickly and isn’t loud. A grunt-snort is coupled with a drawn-out wheezing expulsion of air through pinched nostrils. The buck’s head is tilted up, with ears back and lips curled in a sneer-like facial expression. This is the most threatening call that rutting bucks direct at rivals. It often precedes an antler rush. YouTube has several live deer grunt-snort-wheeze video clips available.
20 | Stress Yawning
Stress yawning behavior is documented in animals such as dogs, horses and bears. I’ve observed yawning on two occasions when two mature bucks had an encounter during the peak of the rut. No does were present in either event. Each seemingly evenly matched pair spent up to 20 minutes in a bluff fest, pawing, rub-urinating, snort wheezing and brush-thrashing displays that eventually ended in a draw. Each time, one buck yawned several times while the other was posturing. Truthfully, it made me chuckle silently. My unscientific assessment was the buck appeared bored and unimpressed. There was never an antler rush made. Eventually the bucks deferred and exited the areas. Were the bucks’ yawns due to stress or fatigue? It’s likely. For sure, Mother Nature never fails to amaze and entertain!
Has your Momma ever given you that look with the lowered eyebrow and clenched jaw that said, "Get yourself in line or else?"
Yeah, most everyone has experienced that at some point. It's called non-verbal communication. It can be paired with any given emotion, but we seem to remember the aggressive stances the most.
Like other animals, whitetails communicate through vocalization, body language, and scent. A deer uses its whole body — ears, eyes, nose, hair, and tail. Whether used singularly or in combination, they serve to warn other deer of potential danger, identify family members, convey family relationships, help find mates and express mood, status, and intent.
The average hunter is familiar with foot stomps and snorts from being busted by a deer, and grunts and bleats during the rut. But view the gallery to expand your knowledge of other ways whitetails communicate and how they can be taken advantage of in your hunting tactics this season.
Facts and Myths About Deer Fawns
My young boys and I were walking across a grassy field on our way down to the riverbank for some fishing when suddenly my son stopped in his tracks. It took him a moment to fully realize what he was seeing, but when he did, he realized we were all standing above a week-old fawn. His first reaction, like that of many people, was that the fawn must be hurt or abandoned, otherwise it would have run off.
The fawn’s mother was not far off, in fact she soon appeared and tried to lure us out of the area. We did not bother the fawn, just enjoyed the moment and then went fishing. Many people have been told that by touching a fawn, your scent will cause the doe to abandon it. This is silly of course, but it’s one of the enduring myths about whitetails. It is often perpetuated by people who want you to leave the fawns alone, and they pass on this myth in their zeal.
If you find a fawn in a vulnerable place, such as a hayfield that is being cut, there is nothing wrong with picking it up and moving it to the edge of the woods. Put it in a shady spot and allow the mother to find it. If the fawn runs off, do not try to catch it, let it find another hiding spot on its own.
The maternal instinct is strong, and the doe will not abandon her fawn because of your scent. Most fawns are half of a pair of twins, so the other one is nearby. The doe may be off feeding, but she won’t be too far.
Most fawns are born during the month of May over most of North America. The southern half of the US and Mexico may see fawn births much later. In northern climates, a fawn born too early may succumb to the frigid nights or a late snowstorm, and one born to late may not be mature enough to make it through the following winter.
By the time fall rolls around, fawns born across the northern half of North America have lost their spots, are weaned and need to be large enough to survive the coming winter.
The breeding season in Texas and Florida are in December and January and are much more drawn out that the short rut found in Canada. Short breeding periods allow the fawns to drop at the best time for survival potential. A fawn born in July in Florida doesn’t have to worry about making it through harsh winter weather which will face a Minnesota fawn beginning in November.
Here’s another myth, there is a belief that fawns do not have any smell so predators can’t find them. Coyotes kill up to 80% of the fawn crop in some areas, and they find the fawns by their scent. Bobcats, wolves, bears and foxes all find young venison to be delicious, and all take their toll on the fawn crop in varying degrees. Coyotes primarily find the fawns by cruising downwind of a likely area with their noses in the air.
The other predators mentioned may occasionally find a fawn by actively smelling for them, but more often have two main tactics for eating fawns. Bobcats, foxes and bears generally find fawns by stumbling across the tasty windfall. Wolves on the other hand, often follow the does around the known fawning areas, waiting until the fawns drop, then quickly gobble them up. There are plenty of cases where wolves and coyotes have been observed actually pulling the partially born fawns out of the mothers. This is fairly common in elk and in moose calving.
The fawns are able to walk within hours after being born, and run within a few days. But they are programmed to lie still rather than run for about three weeks. By the time they are about two weeks old, they can outrun most predators. Fawns spend the majority of their time in hiding for the first month of their life. At about six weeks, the fawn begins to tag along with its mother everywhere she goes.
Fawns will start sampling the vegetation around them at about a month old. They soon discover which plants are good to eat and which are not. They probably learn which plants to eat by observing their mother, as well. But they do not begin to depend on food other than milk until they are about two months old. During the first weeks, their entire life revolves around hiding and nursing.
Fawns have about 300 spots, which offer surprisingly good camouflage, especially when lying in the mottled shade of tall plants. They will carry these spots as long as they wear their summer coats. The spots will not disappear until fall, when the heavy coat of hollow, gray winter fur replaces the reddish summer coat. This usually takes place over the first two weeks in September. The fawns are normally weaned during the month of September as well.
Fawns become sexually mature when they are about six months old. In most areas of North America, the majority of doe fawns are bred during their first November, although some of them may not come into estrus until the early part of December. Young-of-the-year does commonly produce one fawn their first year, then twins in each year after. The availability of quality food and water can alter the number of fawns each doe produces. In areas with plenty of quality food and environmental conditions, triplets are common.
As intriguing as it may be to pick up a young fawn–and no matter how much your boys beg you to raise it as a pet–resist the temptation to make the animal’s life any harder than it already is. The odds are stacked against it. Just enjoy the moment and move on.
Lone Fawns are Not Abandoned
There is a strong probability that you did not find an abandoned fawn. Female deer hide their newborn fawns in tall grass or brush and move some distance away to feed to avoid drawing predators to their offspring. With the proliferation of deer in suburban areas, sometimes this happens right in our own yards. The fawn simply waits in hiding until its mother returns. Soon, the fawns will be strong enough to follow the does and run from predators, and they no longer need to spend hours alone in hiding.
Though it seems that they are vulnerable, these young fawns are not totally helpless. Their spotted pelts look like dappled sunlight on the forest floor and offer great camouflage. They do not have strong scent that would attract predators. Fawns are also programmed to keep totally still and quiet when hiding while their mother forages. The combination of the physical attributes and the behavior of both does and fawns are remarkably successful at limiting depredation at such a vulnerable time.
How does a baby deer stand the day it's born? - Biology
The physiology of reproduction in the deer (family: Cervidae) can help us understand their behavior. Deer are seasonal breeders, with males exhibiting “rut” behavior in the early fall during the breeding season. The timing of the breeding season also has implications in survival of young. Different species of deer respond differently to seasonal changes. However, deer are not the only animals that exhibit seasonal breeding behavior. There are several practical implications of this reproductive phenomenon here, we will look at population control.
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 Male:
The season when deer breed is called the "rut". Rut usually occurs during October, but some bucks come into rut during December, these are usually younger or weaker bucks. It is possible to advance the onset of the breeding season in bucks by controlling their melatonin levels (Adam). Melatonin is a modified amino acid hormone released by the pineal gland that has been seen to control seasonality in ewes. Less daylight triggers an increase in a buck’s testosterone, which causes antler maturation/growth. Fraction, volume and pH of the ejacuate, as well as sperm concentration and sperm motility change gradually during the pre-mating, mating and post-mating seasons of red deer (Gisejewski). The period of greatest libido (from the end of September until the end October) has the highest semen quality.
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 cold out
Mule 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 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.
Reindeer are found in the Arctic and are seasonal breeders. Their breeding season begins in early September and lasts from 3 to 4 weeks. Some reindeer may start breeding as early as late August to accommodate the rough climate and to obtain better nutrition (Alberta Reindeer Association). The gestation period for reindeer is about seven months. Those that will breed early will start fawning in early April. The males will separate into smaller herds during the summer and will all join back up right before the breeding season. As the time for mating drwas near, several changes occur in the male: the testicles and epididymis increase considerably in size, teh velvet is lost form the antlers, the neck thickens, the stomach draws in, and they grow a mane (Alberta Reindeer Association). It is important that the males fatten up before the breeding season because they do not eat much during the season they become thin and may lose up to 1/3 of their body weight (Alberta Reindeer Association).
Roe Deer are located in Scotland, the UK and other portions of Europe. Their breeding season occurs starting in mid-July and continues through mid-August. However, even though mating season occurs in August, the fertilized egg won’t begin to develop until the end of December or early January (Gaillard). It is thought that this occurs to prevent the deer from giving birth during the winter when resources are scarce (Gaillard). Young will be born in May and June and females will give birth to 1-3 young. Twins are also very common in the Roe deer. To attract mates, males will become very aggressive and will defend their territories and will often fight over a female (Gaillard).
Fallow deer are found in Europe, Asia minor and in the United States-especially in Texas (Mammals of Texas). The deer will mate from September to November, with the main breeding time occurring in October. The gestation period is seven and a half months long and fawning begins in late May and lasts through June. Usually only one fawn is born, but twins are common. During the breeding season, males mark off a territory and no other males are allowed to enter (Mammals of Texas). Females will join a male in his territory and will remain there until she comes into heat and mating occurs (Mammals of Texas). After mating season, males will abandoned their territories and will join back with other groups of males.
Comparison to Domestic Animals:
|Species||Type of Estrus|
|Deer||Seasonally Polyestrous- Short day breeder|
|Sheep||Seasonally Polyestrous- Short day breeder|
|Elk||Seasonally Polyestrous- Short day breeder|
|Goats||Seasonally Polyestrous- Short day breeder|
|Horses||Seasonally Polyestrous- Long day breeder|
Understanding reproduction physiology of deer can be helpful in a variety of situations, one of which being population control. It is necessary to control deer populations for many reasons. In 2008, the Wisconsin Department of Transportation reported nearly 16,000 crashes involving deer (Wisconsin Dept. of Transportation). The Wisconsin Department of Natural Resources reports that in 2008, 84.5% of the approximately $2.1 million in appraised losses from wildlife were from deer damage. Damage to corn and soybeans accounts for approximately two thirds of this (Wisconsin Department of Natural Resources). Some organizations also argue that deer populations have risen to a point where the habitat can no longer support the large numbers. Another concern with a large population within an area is the high risk of transmitting disease throughout the herd. Measures that have been taken to help control deer populations include restrictions on hunting, relocating individuals, and even birth control. Both chemical and mechanical methods have been used to attempt to prevent pregnancy in deer. Estrogens or progestins, fed orally during the breeding season, have not been reliable enough to apply to an entire population. Mechanical methods have included tubes containing either an estrogen or progestin implanted subcutaneously in females. The limitation with these has been that the biological life of the implants has not been determined beyond 150 days (Matschke).
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