UPLAND V( ILDLIFE ECOLOGY 



Resident game in the Fnited States, both birds 

 and nianiiniils, is produced largely on privately 

 owned land, and responsibility for its management 

 lies primarily with the State game and fish de- 

 partments. The Bureau has clear responsibility 

 for researcli on prol)lems atfecting the public lands 

 and, for the most part, the work is done coopera- 

 tively with ])ersonnel of the Forest and Range Ex- 

 |)eriinent Stations of the U.S. Forest Service. 

 Bureau research on farm game is carried on prin- 

 cipally through the Cooperative Wildlife Re- 

 search Units, in direct cooperation with the State,s. 



Deer dispersal. — Results from a mule-deer- 

 tagging study in Utah by a Denver Center bi- 

 ologist re\ealed the imjx>rtance of dispersal as a 

 means of replenishing stocks on areas decimated 

 ihiongli hunting. A 3-square-mile tract in the 

 lieart of the Oak Creek sunniier i-ange had con- 

 sistently pnxluced high annual kills of over 30 

 animals per section, iis compared witJi only S per 

 section elsewiiere on the sunuuei- i-ange. Further 

 analyses revealed that the net annual production 

 of deer on the 3 square miles was about fiO versus 

 a kill of 9(1, while on adjacent summer I'anges pro- 

 duction exceeded the annua] kill, or 12 and 8, re- 

 sj>ectively, j)er serf ion. The degree of dispersal 

 appeared to be more closely associated with carry- 

 ing capacity than with population density perse. 

 Dispersing deei- a])parently wandered about at 

 random until they located an area with minimal 

 competition for fiMid and cover. 



Efjrrt of (her hroirshu/ on roniferx. — At two 

 exclosure sites on the Tamarac National Wild- 

 life Refuge in Minnesota, established to measure 

 effects of deer browsing, findings show that ex- 

 cessive munbei-s of deer are capable of killing anil 



retarding the gi'owfh of young pine trees. At one 

 red pine plantation the loss was 83 percent for 

 trees subjected to deer browsing as compared with 

 40 percent for trees in an exclosure. The fenced 

 trees also grew more than twice as high (13.!) feet 

 versus 5.4 feet). Outside the exclosure, the aver- 

 age diameter at breast, height was less than half an 

 inch, and all trees were of poor quality. In con- 

 trast, 34 of 36 protected trees were of crop quality, 

 and the average diameter was 2.6 inches. In a 

 natural stand of jack pines, the stocking of young 

 trees increased 50 {>ercent on an unprotected area, 

 but about 500 percent in an exclosure. Breast- 

 height diameter of fenced trees was 1 inch greater 

 (2.6 inches versus 1.6 inches). The exclosure 

 contained 17 percent more trees of crop quality. 



Phyxiolofi'/caJ studies of the white-tniled deer. — 

 Six 2-year-old male deer were used In^ the Pennsyl- 

 \ania Unit ami cooperators in radioisotope experi- 

 ments to study the utilization of phosphorus 

 (P'-) i>efore. during and after antler growth, 

 .'inalyses of tissues, bone, antlers, and excreta of 

 all aiiimals indicated that (1) I"= (as NaJTP^-4) 

 was rapidly absorbed after intraruminal injec- 

 tions, (2) high concentration of P''- was deposited 

 in the Imjiu's of the head in all animals, whether or 

 not antlers were growing, and (3) rates of dep- 

 osition in other bones and tissues were smaller 

 and varied, a])parently in relation to degree of in- 

 \olvement of the tissue in phosphorus metabo- 

 lism. Iri nary excretion was small (<1 percent), 

 but fecal excretion accounted for as much as 30 

 |>erceiit of the dose. 



Added day length (artificial light) delayed the 

 antler ruboiit and shedding dates 10 to 11 days. 

 The normal drop in feed consumption during the 



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