pressure likely of achievement. Although 

 hunters generally avoid killing fawns if 

 possible, data from other areas indicate 

 that fawns comprise 15% to 20% of the kill 

 in antlerless hunts. The annual kill of 

 36,000 would probably require private 

 lands to be hunted as heavily as public 

 lands. Comparison with Strategy 2 indi- 

 cates that the hunting kill would increase 

 about 45% , even though the overall popu- 

 lation decreases about 40% . Natural losses 

 are also much reduced. 

 4. Fifty Percent Bucks, Fifteen Perceyit Does, 

 a)id Si.vty Percent Fawns: While the previ- 

 ous strategy would tend to maximize the 

 hunting kill if hunters were allowed their 

 free choice of animals, the kill could be fur- 

 ther increased by selectively hunting fawns. 

 This strategy is comparable with the usual 

 sheep management regime in Mendocino 

 County, where a high proportion of lambs 

 is marketed annually. Although the kill 

 would be considerably higher than in the 

 previous strategy, the total biomass yield 

 would be slightly lower because of the 

 relatively small size of fawns. It may be 

 unrealistic to propose that 50% of the 

 bucks can be killed annually. However, 

 if the goal of management is to maximize 

 the number of animals taken by hunting, 

 it is necessary to maintain the highest 

 possible proportion of breeding does in the 

 herd, and this can be achieved only by 

 heavy hunting of adult males. 



A convenient way of showing hunting yield 

 and population numbers at equilibrium for 

 different strategies is by plotting the results 

 from many computer runs on graphs like these 

 shown in Figures 4 through 6. These graphs 

 permit a comparison of the relative effects of 

 selective hunting pressure directed against 

 does, fawns, and buck, respectively. 



Figure W- This graph depicts population 

 trends and yields of deer when various per- 

 centages of does are taken by hunting when 

 (A) no bucks or fawns are taken, and (B) 50% 

 of all bucks and 15%- of the fawns are taken an- 

 nually. Several pertinent aspects of population 

 performance are apparent from this graph: 



(1) With no hunting of bucks and fawns, a 

 slightly higher total population of deer 



tends to be maintained when any given 

 removal of does is carried out. 



(2) Maximum productivity or yield of the 

 population is achieved when approximate- 

 ly 25% of the does are removed annually. 

 However, the total yield is approximately 

 five times higher if bucks and fawns are 

 taken as specified in Strategy (B). 



(3) As hunting pressure on does increases, 

 overall deer numbers decrease at an in- 

 creasing rate. 



Figure 5: Figure 5 indicates the effect of 

 increasing fawn removals accompanied by (C) 

 no buck or doe hunting, or (D) annual hunting 

 removals of 50% ofthe bucks and 30%. of the does. 

 It shows that: 



(1) The total population will decline only 

 slightly with the increasing removal of 

 fawns only, as depicted by (C). 



(2) Under the buck-doe strategy in (D), 

 maximum yield and population size will 

 diminish rapidly if annual fawn removal 

 exceeds approximately 30% . 



Figure 6: The hunting conditions set forth 

 on this graph are, (E) no does or fawns are 

 taken as related to the increasing take of bucks, 

 and (F) a removal of 30% ofthe does and 15% of 

 the fawns in relation to an increasing take of 

 bucks. The graphs show that: 



(1) Buck removal alone has only a slight 

 effect on yield, and even less effect on 

 total population. 



(2) When does and fawns are taken as speci- 

 fied in Strategy (F), the total yield of 

 the population is roughly doubled, as com- 

 pared to taking bucks only. 



GENERAL RELATIONSHIPS 



Consideration of the three graphs shows that: 



(1) Maximum yield ofthe Mendocino County 

 deer population is only achieved through ex- 

 ploitation. 



(2) Reduction of the large, unexploited popu- 

 lation through hunting produces a more dy- 

 namic population, with greater turnover. The 

 basic relationship is to lower stocking rate 

 on the range, which reduces competition for 

 available feed, and thereby raises the plane 

 of nutrition. This, in turn, improves fecundity 

 and survival. 



129 



