Ask the Biologist

Have a question regarding deer or deer biology?  Below are some questions posed by visitors and answered by branch biologist, Dick Henry.  If your question isn’t listed, feel free to submit a new question using the link below.

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1. Last year I harvested a deer that had several hard black growths in and on its skin. What causes this?
2. Isn’t Lyme disease spread by white footed mice, not deer?
3. Is a spike buck always going to be a spike buck ?
4. Do antler restrictions really work? I have heard so many rumors (and opinions) that it makes me confused. Whats the real deal?
5. What are the most critical months of the year for deer and why?

1. Rating: +7

   

   Last year I harvested a deer that had several hard black growths in and on its skin. What causes this?

   What you saw is called a "fibroma" or "papilloma". It is a hairless external black or grey tumor that is caused by a virus transmitted into the skin of the deer when it is bitten by an insect, most commonly a deer fly. They are attached to the surface of the skin and are generally not a problem for the deer unless they become infected (rare) or become so numerous that they interfere with the deer's vision, locomotion or eating.

   Fibromas are not contagious and cannot be transfered to humans or pets. While grotesque and unsightly, fibromas also do not affect the meat and should generally just be cut off at the surface of the skin and discarded before butching the deer. The attachment of the fibroma often recedes and I've seen them in late spring where they appear to be hanging by a stalk. Interestingly, the virus that causes cutaneous fibromas appear to be specfic to deer and are not observed in cattle, horses or other livestock.

   Don't let it spoil your deer hunt !

2. Rating: +4

   

   Isn’t Lyme disease spread by white footed mice, not deer?

   You are correct in that white-footed mice are the primary reservoir of the bacterium Borrelia burgdorferi that causes Lyme disease. The deer tick or black legged tick, (Ixodes scapularis) first acquires the bacterium when it takes a blood meal from an infected white footed mouse. Once infected, the deer tick then becomes the predominant vector responsible for the spread of Lyme disease.

   Deer ticks go through three progressive life stages before becoming an adult. They are quite small and the nymphs or early life stage are almost microscopic in size. Once infected, deer ticks can then pass the bacterium and the disease to other mammals, including humans, whenever they bite a new victim and take in a blood meal in later life stages.

   White-tailed deer are commonly thought to be the only carrier of deer ticks. However, in reality many other species of mammals and birds can also acquire and carry deer ticks. Dogs and cats routinely pick up deer ticks and can readily bring them into contact with humans.

   Deer are simply one of many animals that carry and spread ticks that may harbor Lyme disease.

3. Rating: +7

   

   Is a spike buck always going to be a spike buck ?

   “Once a spike, always a spike” was a common refrain I heard when going afield with my deer hunting elders in Ulster County in the late1950’s. Nothing could be farther from the truth - a yearling buck with spike antlers is similar to a 12-year-old boy…an energetic, excitable and highly mobile individual with a lot of growing that needs to occur to his physical stature before he reaches maturity.

   Spike bucks in New York State are almost always a yearling deer and are not destined to be spikes if they survive to future hunting seasons.

   For more on this answer, read my blog: Once a spike, always a spike

4. Rating: +0

   

   Do antler restrictions really work? I have heard so many rumors (and opinions) that it makes me confused. Whats the real deal?

   The short answer to your question is “yes” antler restrictions can and do work. This has been proven time and again in many portions of white-tailed deer range in North America. In fact there are currently a total of 21 other states besides New York with white-tailed deer that currently have antler restriction programs implemented in their area of jurisdiction.

   Click here to read my full blog on Antler Restriction

5. Rating: +10

   

   What are the most critical months of the year for deer and why?

   Aside from the fall hunting season when half a million hunters are afield in New York State, the most critical months for deer survival are late winter, especially when weather conditions have been harsh for an extended period of time.

   Read Dick's expanded answer on Deer Mortality