Could This Deer Fawn Survive Without Its Mother?

A fawn hops in the backseat of a police car before reuniting with its mother. But what if this reunion hadn't happened? Could this fawn survive?
Could This Deer Fawn Survive Without Its Mother?

Featured photo: Wikimedia Commons (Veledan)

A deer fawn in Marin County, California, hopped in a police officer’s car and took a good whiff of the cop’s coffee.

The fawn should be commended for making a wise choice. Only moments earlier the young deer was trapped in the middle of a busy highway as commuters halted traffic and attempted to avoid hitting the small animal. A doe stood nearby, off the road, looking on at her fawn.

Video posted to the Marin County police department’s Twitter feed captures the brief encounter. The fawn was able to get in and out of the car much faster and more effectively than your common criminal. Once free of the car and its tempting cup of joe, the police officer scooped the fawn up and reunited it with its mother. The two scampered off together.

Could This Fawn Have Survived Without Its Mother?

Let's say the scenario had played out a bit differently. Perhaps the fawn was rescued, but the doe disappeared and the reunion never happened, then what? The answer depends on the age of the fawn.

Typically, fawns are born in California in late spring to mid-summer and are spotted at birth, but lose their spots within a few months. The fawn in the video still had its spots so, given that we're just now moving into the latter part of the spring season, this fawn is theoretically only a month or two old.

If we make assumptions based on the average, then we can estimate this fawn was about 6 weeks, or 42 days old at most. According to the Quality Deer Management Association (QDMA), fawns can be weaned at 10 weeks of age (70 days). It's not unusual for fawns to be seen nursing after 70 days, but some biologists believe it's more of a bonding exercise than a nutritional requirement.

"From a body development standpoint, fawns are functional ruminants well before the 70-day weaning and can therefore forage on their own much earlier," said Kip Adams, QDMA's director of conservation. "Fawns that are 45 to 60 days old are typically old enough to survive, although additional learning opportunities from mom are always advantageous. This is especially true in light of increasing predator populations in many areas.

"Since fawns don’t wear name badges with their birthdates, a great way to determine in the field whether they’re likely old enough to survive is to look for the presence of spots."

Our coffee-loving sweetheart still had its spots, so chances are slim that the young deer would have survived without its doe.

Survival Rate of Deer Fawns

There have been numerous studies over the years offering some idea of a fawn's survival rate. More recently, these studies have increased, especially in states where whitetail deer are prevalent and in the South where fawn survival rates continue to decline. One of the most recent studies on deer in Pennsylvania showed a 52 percent survival out to 10 weeks. Of all the collared fawns killed, three were eaten by black bears, three by bobcats, one by a coyote, one by a dog, three from unknown predators (DNA results pending), five from natural mortality and one by car.

Other studies had varying results. As reported by Whitetail Journal: A North Carolina study showed only 5 of 27 collared fawns (18.5 percent) made it to 16 weeks. Fifteen of the 22 mortalities were caused by coyotes or bobcats and 55 percent of the mortality occurred the first week of life.

Two Alabama studies showed a 33 and 31 percent fawn survival out to 16 weeks, which isn’t good. A Georgia study showed a 29 percent survival and a South Carolina study showed a 22 percent survival of fawns. Even worse.

Things aren’t as bad further North, although coyote numbers are increasing there. In Ohio, a relatively recent study showed coyotes were responsible for 19 percent of mortality. Natural causes claimed 22 percent and in many cases most of those in the natural death category died from starvation.

One critical factor in declining fawn survival rates is the increase in predation. For the first time in the past 100 years, we have a myriad of predators in the eastern half of the United States.

"Black bear numbers continue to climb and they are spreading their range as well," wrote Dr. Dave Samuel in a column for Whitetail Journal. "Bears do eat fawns, but at least two studies concluded that black bears were 'opportunistic' predators on deer fawns. They do not seek them out, but eat them when they find them. In most areas, it appears they are not responsible for more than 10 percent of fawn mortality, but when combined with other predators, it adds up."

Samuel also cited the rising numbers of bobcats. In some states, these populations are at an all-time high. An on-going study in northern Michigan noted bobcats took a surprising number of deer, perhaps because of deep snows in winter. In some areas they take more fawns than coyotes, but in most areas they don’t.

Ultimately, Samuel offers these concluding thoughts on fawn mortality: "Fawn mortality studies can be frustrating and a bit complicated. We know fawn mortality is lower for fawns with healthy mothers. Do healthy mothers have fewer fawns killed by predators?  We don’t know, but we do know fawn mortality is lower when they are born in a high-quality habitat. Such habitat is usually found where deer numbers have not exceeded the carrying capacity. Maybe more ground cover means better fawn hiding cover.

"What we now know is that getting that fawn through the first week of life is critical to its survival."



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