BSK - Drought and Antler Development?

[WMAn]

I was very intrigued by the pictures posted by Andy S. on this thread:

http://www.tndeer.com/tndeertalk/ubbthr ... =0&fpart=1

It seems like a lot of bucks with large bodies and relatively underveloped antlers. Knowing that they had a severe, localized drought around Ames this summer, is the large number of bucks that fall into this category a result of the dry conditions?

How much of an effect will a dry summer have on antler development?

Will a relatively normal year that follows remedy the problem?

 

[8 POINTS OR BETTER]

Very good questions.

 

[BSK]

WMAn,

First let me say this in bold caps, MUCH ABOUT ANTLER DEVELOPMENT IS LITTLE UNDERSTOOD. So much about why individual bucks grow particular antlers is not known. The exact process of antler growth is not something that has been scientifically deciphered.

To comment on those pictures, I would need to see all of Ames' data. I know they have been conducting photo data collection for years for the purpose of assessing antler development per age-class. The information I would need to see is the "bell-curve" of antler scores collected for mature bucks in the area. Are the small-antlered bucks in ANdy's pictures truly unique for just last year or are they just the normal "left-hand-side" of the curve?

Perhaps these smaller than expected antlers on mature bucks really are unique to last year. But I suspect they are not. I suspect they are just a demonstration of just how much variability Nature produces for any physical characteristic.

How much of a role nutrition plays in antler development, and when the critical phases are for nutritional intake, are much debated topics. Some Southeastern research strongly suggests that winter nutrition is just as if not more important than summer nutrition for antler growth. In essence, the condition of a buck before spring green-up may be more important to antler growth during the upcoming summer than what that buck eats during summer.

This doesn't mean a summer drought isn't harmful to antler development. It certainly is. But even great summer growing conditions may be muted by poor buck health during the previous winter. A "bad antler year" may be linked to the previous fall and winter's food sources more than summer food sources.

 

[8 POINTS OR BETTER]

BSK,
What are your thoughts on one very bad year like 2007 setting a deer back as far as antler growth and body size for the rest of his life. Say a deer survied the spring freeze, the drought, and EHD all in one year. How much potential could a year like that take out of a deer.

 

[BSK]

BSK,
What are your thoughts on one very bad year like 2007 setting a deer back as far as antler growth and body size for the rest of his life. Say a deer survied the spring freeze, the drought, and EHD all in one year. How much potential could a year like that take out of a deer.

Severe growing conditions would have the most long-lasting impacts on the youngest deer, especially fawns. They are attempting to grow larger in all dimensions (bones ae still growing longer) hence malnutrition would have the greatest long-term impact on the youngest age-class.

If we were looking for long-term affects from the severe spring/summer/fall of '07, the bucks that would display the greatest impact would be bucks that are 3 1/2 this year (fawns in '07), and secondarily 4 1/2 year-old bucks this year (yearling bucks in '07).

Of interest, I did notice unusually small 3 1/2 year-old bucks this year, both in body and antler.

 

[WMAn]

BSK,

Thanks for the great responses.

 

[Andy S.]

If we were looking for long-term affects from the severe spring/summer/fall of '07, the bucks that would display the greatest impact would be bucks that are 3 1/2 this year (fawns in '07), and secondarily 4 1/2 year-old bucks this year (yearling bucks in '07).

Of interest, I did notice unusually small 3 1/2 year-old bucks this year, both in body and antler.

X2...I have mentioned this to several friends/hunters this year in an attempt to suggest that the '07 drought may have negatively impacted the 3.5 and 4.5 year old class of bucks in more ways than we can understand, or ever know. I have no scientific proof to support my claim, just the theory that the severe drought that year may have had detrimental long term impacts on those age deer.

 

[8 POINTS OR BETTER]

If we were looking for long-term affects from the severe spring/summer/fall of '07, the bucks that would display the greatest impact would be bucks that are 3 1/2 this year (fawns in '07), and secondarily 4 1/2 year-old bucks this year (yearling bucks in '07).

Of interest, I did notice unusually small 3 1/2 year-old bucks this year, both in body and antler.

X2...I have mentioned this to several friends/hunters this year in an attempt to suggest that the '07 drought may have negatively impacted the 3.5 and 4.5 year old class of bucks in more ways than we can understand, or ever know. I have no scientific proof to support my claim, just the theory that the severe drought that year may have had detrimental long term impacts on those age deer.

I think it may have effected this years 2.5 year olds, because the does that did gave birth in the spring of 2008 where in such bad condition.

 

[WMAn]

Speaking in generalities then:

Best For Antler Development

A heavy mast crop especially red oaks in the fall/winter that is followed by a wet spring and summer. Or spring/summer conditions that produce above average yields for area farmers

Worst for Antler Development

Mast crop failure. (I saw this once at LBL; based on tracks and droppings you would have thought every deer on the place had been fenced in and around the cut bean fields.) Followed by a prolonged drought or spring/summer conditions that result in crop failures for area farmers.

Assuming that native browse will benefit or be negatively impacted by the same factors that affect corn and soybean yields. Are these best and worst case situations generally going to be right?

 

[mallard239]

i would like to see some numbers on the ph of the soil on the crop fields at ames. i know in the test plot data that ut extension puts out, you can always count on ames' yields to bring up the rear, by a long shot.

 

[BSK]

If we were looking for long-term affects from the severe spring/summer/fall of '07, the bucks that would display the greatest impact would be bucks that are 3 1/2 this year (fawns in '07), and secondarily 4 1/2 year-old bucks this year (yearling bucks in '07).

Of interest, I did notice unusually small 3 1/2 year-old bucks this year, both in body and antler.

X2...I have mentioned this to several friends/hunters this year in an attempt to suggest that the '07 drought may have negatively impacted the 3.5 and 4.5 year old class of bucks in more ways than we can understand, or ever know. I have no scientific proof to support my claim, just the theory that the severe drought that year may have had detrimental long term impacts on those age deer.

Although you can't say much from a sample of one, the 3 1/2 year-old buck I killed this year was healthy in most visible traits (fat deposits), but 3 1/2 year-old bucks from my area normal live weighs around 200 lbs, yet this buck only live weighed 168 pounds. That's the lowest body-weight 3 1/2 year-old buck we've ever killed.