Wednesday, May 16, 2012

Understanding Fawns And Knowing To Leave Them Be

No good comes from mothering nature anywhere in Pennsylvania

By Joe Kosack
Wildlife Conservation Education Specialist
Pennsylvania Game Commission

HARRISBURG – It’s an annual chapter in nature that begins in May, peaks in early June and always goes largely and surprisingly unnoticed. But with time, the annual birth of hundreds of thousands of white-tailed deer has the potential to influence the lives of most Pennsylvanians and many wildlife species.

Whitetails represent one of the Commonwealth’s most vibrant and valuable natural resources, but also serve as one of its most problematic. The complexity of their management is closely tied to their health, habitat and conflicts with people. This is compounded further by the whitetail’s inherent adaptability and resilience and the desire of many Pennsylvania hunters – who primarily finance wildlife conservation – to see more deer afield.  

            When fawns hit the ground in Pennsylvania, they start a journey that millions before them have taken. It begins in a quiet section of field or forest, and sometimes, even a backyard, but eventually leads deer to almost every open acre of land in the Commonwealth. They can be found wandering in the open spaces and parks of Philadelphia and Pittsburgh; roaming our agricultural fields and deep forests; sloshing through our swamps and waterways; and taking comfort wherever they find it. That coverage ensures fawns will pop up almost anywhere in spring, seemingly out of place and parentless. But they’re not.

Fawns use a “hider” strategy when born; they lay curled motionless and quiet in the weeds and on the forest floor.  Their spotted coats provide camouflage, they emit relatively little scent and they rarely travel their first few weeks. The parenting doe leaves her fawns to forage regularly and returns periodically to nurse her hiding fawns. So, it is not unusual to see fawns unaccompanied by an adult deer in late May or June.  At about a month old, fawns start traveling with their parents.

Research shows about 65 percent of fawns make it through their first two months. Most making it through this critical period go on to represent about a third of the state’s overall deer population and their addition offsets the losses from hunting and other mortality factors in the previous year.

“Fawn recruitment has sustained Pennsylvania’s deer herd for decades,” noted Dr. Christopher Rosenberry, Game Commission Deer and Elk Section supervisor. “Even though some fawns die annually, it is the norm in Pennsylvania and elsewhere. Their annual addition to the deer population must equal or exceed the number of deer removed for a deer population to remain stable, or to increase.”

The Game Commission examines tens of thousands of deer taken each year during the statewide firearms seasons for whitetails. Through this analysis, deer managers keep tabs on the percentage of fawns in the harvest – and, ultimately, the statewide population. This work would uncover if predators or some other mortality factor was causing an unacceptable level of harm to fawns or the overall deer population. It hasn’t, for decades.

Fawns confronted with peril in their first several weeks usually escape it. The danger may come from exposure, sickness, parental abandonment, predation, loss of parent, or being struck by farm machinery. Fortunately, many of these mortality threats largely are escapable, but even when they aren’t, fawns don’t flee a closing danger. Their natural response is to remain in a fetal position and motionless. That makes them susceptible to prowling predators, such as black bears, coyotes and other predators, ranging from dogs to even fishers.

            “Our deer have continued to thrive in the face of expanding black bear and coyote populations over the past two decades,” Rosenberry noted. “Annual statewide deer harvests reflect this. Whitetails are extraordinary adapters. They can survive on landscapes densely populated with humans and increasing numbers of predators.”

Field research has shown that predation has never been a significant fawn mortality factor in Pennsylvania. That’s probably related to the tremendous supply of other prey and seasonal foods at the time; the amount of effort required for a predator to find and take a fawn; and the narrow time slot in which most fawns are born and remain most vulnerable to predators.

During a fawn mortality study conducted in 2000 and 2001 by the Game Commission, Penn State University and Pennsylvania Fish and Wildlife Research Unit, similar numbers of fawns – less than three weeks old – were captured and radio-collared in Penns Valley (agricultural landscape) and the Quehanna Wild Area (forested landscape). No relationship was detected between fawn survival and habitat or landscape features. After 34 weeks, predation accounted for 49 of 106 mortalities that were sustained by the 218 study fawns. Coyotes took 18 fawns; black bears, 16. The study concluded fawn survival in Pennsylvania was similar to rates from studies in other northern states and that overall fawn mortality in the Commonwealth was not preventing population growth.

“This study and others that followed showed clearly that after a fawn makes it through its first summer, the greatest threats to its survival were from hunters and moving vehicles,” explained Rosenberry. “In other studies across Pennsylvania, we have captured and marked thousands of adult deer. Confirmed predator mortalities for those adult deer can be counted on one hand.”

Most fawns are born within a week of Memorial Day, which leaves a sudden and incredible number of them curled up in the weeds and woods statewide. The plethora of young deer all but ensures death will not consume the majority in this massive recruitment effort.

At birth, an average fawn is about 7.5 pounds, the weight of a small housecat. At one month, about 23 pounds. Consequently, it’s not hard to visualize their vulnerability early in life. That’s why this wobbly-legged fawn employs the hider defense, rather than run. Emitting little odor and being tucked into the vegetation has its advantages, too.

A doe feeding fawns needs to consume large quantities of food to fuel their rapid growth and milk lifeline. That means she has to forage often, leaving her fawn(s) unattended – bucks do not assist in raising young – and at risk. It’s almost always when the doe is away that people bump into fawns. If they’d leave these young deer where they find them, the fawns would be fine. But they don’t, and no good ever comes from removing a fawn from the wild.

“Everything changes the moment a fawn is taken from its natal area,” explained Rosenberry. “Its absence – coupled with lingering human scent – is treated as a loss by the returning doe after a short search. It’s just another adjustment for her in the world of whitetails. She moves on, possibly caring for her other fawn, and the abducted fawn is separated from its natural parent for life.”

People who care about wildlife can best help fawns and other young animals by leaving them alone. If they appear out of nowhere, distance yourself from them immediately. Reassure yourself that they’ll be fine without your assistance. And then stay away from the area – pets included – for a few weeks to allow nature to run its course.

Fawns grow quickly. Within two months, they’ll be cruising with adult deer, eating and nibbling from nature’s smorgasbord and learning life’s lessons. Their increased size and mobility provide that edge they need to mature. And most do, so long as they weren’t removed from the wild by someone wanting to mother nature.

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