The primary goal of my study was to evaluate strategies for promoting local support for wildlife conservation in Masai Mara National Reserve (MMNR) and the adjacent group ranches. This was done by determining the effects of the changing land tenure from communal to individual on the Maasai lives and wildlife, and the role of the revenue sharing program in enhancing support for wildlife conservation. The study used local people's suggestions to recommend strategies for improving revenue sharing. A combination of literature review, questionnaire-based surveys and participant observation methods were used to achieve these goals. The maintenance of a viable ecosystem in Mara has succeeded due to the traditionally benign relationship between the Maasai and wildlife. However, various factors continue to strain this relationship. First, increasing human population and encroachment of agriculture has diminished areas available for livestock and wildlife grazing. Second, the absence of compensation for loss of life and property to wildlife and inadequacy of the revenue sharing has increased people's antagonism towards wildlife. Third, since the local people are excluded from the management of MMNR and wildlife in general, they consider these activities external impositions. Fourth, subdivision of group ranches will severely reduce the land available for livestock and wildlife grazing and eliminate the traditional resource sharing strategy that has sustained the Maasai for centuries. This study also revealed that although the Maasai harbor many negative feelings towards MMNR, they consider it an important asset. Further, they are unwilling to give up pastoralism and expect to continue with communal grazing after subdivision which, is good for wildlife conservation. In view of this, I made the following recommendations: implement a regional land management system with a core wildlife area (the reserve) and a wildlife management-pastoral area surrounding the core, and designated zones for agriculture; support the above system with firm government policies and incentives; redesign the revenue sharing program to cover all the affected people; promote policies that encourage diversified wildlife-based enterprises including consumptive use; transfer much of the wildlife management responsibilities to the local people.

A study of the coyote in southern Arizona was initiated to gain insight into basic ecological relationships and to provide a basis for more detailed future studies. The behavioral portion of the study was conducted on the Santa Rita Experimental Range (SRER), where apparent minimum home ranges for 6 radio-tracked coyotes ranged in size from 0.5 to 7.9 square miles, and averaged 4.2 square miles. The relatively small home ranges may have reflected high coyote density and abundance of food during the period of study. Females tended to occupy larger areas than did males. Home ranges appeared to be a composite of foraging ranges, each of which had its own center of activity. Generally home ranges exhibited the property of linearity. Coyotes typically became active before dusk and remained so until midmorning of the following day, with cooler weather extending activity periods. Based upon annuli counts from canine teeth of 378 coyotes, the age distribution within the general population was as follows: 0-1 year old, 32.8%; 1-2, 14.3%; 2-3, 15.3%, 3-4, 12.2%; 4-5, 11.4%; 5-6, 5.0%; and over 6 years, 9.0% of the sample. The average age was 3.2 years (s.d. 2.4), with one animal reaching just under 14 years of age. Subsamples representing different years, causes of death, and counties had significantly different age class distributions. Also, coyote age class structures from various regions of North America exhibited highly significant variations. Of 273 known-sex coyotes, the ratio was 154 males: 119 females. Males tended to outlive females; for coyotes over 5 years of age males significantly outnumbered females. The control practices of trapping and poisoning killed a highly significant majority of male coyotes. Hypothetically, disproportionate sex ratios were part of a mechanism whereby coyote populations maintained a balance with their environment. Reproductive tracts from 22 males and 20 females were examined. Males produced spermatozoa from January to June. There was no evidence of breeding among juvenile females. Over 100 coyote specimens were examined for parasites. Information on the occurrence of ectoparasites tended to be of qualitative value. The species identified were Pulex simulans, Echidnophaga gallinacea, Thrassis arizonensis, Heterodoxus spiniger, and Otobius megnini. The 15 species of helminths recovered consisted of 5 cestodes, including Taenia pisiformis (56% infection rate), T. multiceps (22%), T. macrocystis (6%), T. hydatigena (1%), and Mesocestoides sp. (6%); 8 nematodes, including Ancylostoma caninum (38%), Filaroides osleri (3%), Toxascaris leonina (43%), Physaloptera rara (51%), P. sp. (1%), Rictularia cahirensis (3%), Mastophorus numidica (1%), and Dirofilaria immitis (2%); and 2 acanthocephalans, including Oncicola canis (46%) and Pachysentis canicola (1%). Pups and females were subject to greater collective endoparasite burdens. Variations in incidence and intensity of infection were also noted with year, season, and county. A general picture of food habits was obtained by examining 101 coyote stomachs. By percentage of overall volume, stomach contents were: larger mammel, 25.4%; smaller mammal, 35.0%; bird, 16.4%; reptile, 0.1%; invertebrate, 6.4%; and vegetable matter, 16.2%. Much of the larger mammal material was carrion. Statistical analyses revealed that there were significant differences in the diets of pups and females versus adults and males, respectively, while variations in diet between years, seasons, and counties did not appear significant. By percentage of organic weight, contents of 619 coyote scats from the SRER were: larger mammal, 15.8%; smaller mammal, 49.9%; bird, 0.8%; reptile, 0.2%; insect, 5.4%; and vegetable matter, 27.9%. Variations in recovered weights of the major food categories between seasons were highly significant. The proportion of native fruits and insects in the scats increased greatly in summer and fall, and appeared responsible for moderating predation upon smaller mammals for several months.

No description available.

No description available.

In contrast to documented increases in woody plant dominance of former savannas and grasslands of North America, oak (Quercus L.) savannas that form lower treelines in the southwestern United States and northwestern Mexico have been relatively stable over the past millennium. This research identified potential biotic and abiotic constraints on seedling recruitment of Quercus emoryi Torr. (Emory oak) within the context of potential shifts in lower treeline. Field surveys were used to describe seedling distribution at and below lower treeline, and to determine the potential for acorn dispersal from lower treeline into adjacent grassland. Field and greenhouse experiments designed to determine constraints on seedling establishment included reciprocal soil transfers, nutrient amendment studies, provision of artificial shade, and manipulation of seasonal precipitation inputs. Results indicate that rates of Q. emoryi recruitment within grasslands below treeline are relatively low, and are constrained by low rates of seed dispersal coupled with a low probability of seedling emergence. Seedling recruitment rates were directly correlated with quantity of summer precipitation, but were independent of winter precipitation. Results of this and complementary research suggest that lower treeline in southern Arizona is stabilized by self-enhancing feedback mechanisms of overstory shade, seed dispersal, and seedling establishment coupled with strong abiotic constraints beyond the current ecotone. The observed shift in treeline in the last millennium was less likely the result of slow, spatial progression of autogenic safe sites than the result of episodic and infrequent allogenic processes that simulated, or negated the importance of, conspecific, biogenic safe sites. Increases in summer precipitation are one such process that would facilitate (historic or potential future) downslope shifts in lower treeline. This interpretation is consistent with observations that downslope shifts in lower treeline which occurred 700-1700 ybp coincided with a period of particularly high summer precipitation in the region (i.e., the "Medieval Warm" period, 645-1295 ybp).

Conservation partnerships are working throughout the United States to address natural resource problems in watersheds. These projects have levels of complexity that challenge successful accomplishments. This study investigates what constitutes success in watershed partnerships and what measures may define success. Characteristics are identified from a literature search to create a success model. Characteristics of three partnerships led by the U. S. D. A. Natural Resources Conservation Service, Conservation Districts, and Resource Conservation and Development councils are compared to the model. Analyses address frequencies of occurrence of characteristics and differences between public and private responses. The results do not support the success model. Eight common characteristics of success are found in the case studies. Six of these characteristics are of a qualitative nature indicating a need to include qualitative measures with quantitative measures of success. The development of an effective guide for successful conservation partnerships is based on the eight characteristics.

Sap flow, leaf gas exchange, and micrometeorological parameters were evaluated during 1997 in riparian forest at perennial and ephemeral stream sites on the San Pedro River in southeastern Arizona, USA. At the perennial stream site, measurements of sapwood area based transpiration and sapwood area/canopy area of clusters of Populus fremontii and Salix goodingii were used to estimate transpiration across the stand. Stand structural heterogeneity resulted in as much as 30% variation in mean transpiration across the stand. Transpiration of cottonwood was more dependent upon vapor pressure deficit at the ephemeral stream site which had an open, less dense canopy compared to that at the perennial stream site. This may be due to differences in advection properties and canopy feedback processes between sites. Conversely, transpiration in willow was less dependent upon vapor pressure at the ephemeral stream site than that at the perennial stream site. This may be due to water stress associated with deeper depth to groundwater.

Yellow bluestem (Bothriochloa ischaemum (L.) Keng.) cultivars are used in conservation plantings in New Mexico, Texas and Oklahoma. The recommended cultivar in southern Arizona is Ganada. However, a population from Saudi Arabia P.I. 237110, may be better adapted to the Sonoran Desert environment. This study was conducted to determine why P.I. 237110 may be better adapted to this environment than Ganada. Morphological and physiological characteristics of P.I. 237110 and Ganada were compared in five experiments. Evaluations revealed significant differences in combined stomate densities on both leaf surfaces, leaf surface area, and water use efficiency but not in apparent photosynthesis or dark respiration. Combined average stomate density was significantly lower for P.I. 237110 than Ganada (107 vs. 136 stomates mm⁻²). P.I. 237110 had a significantly higher leaf surface area (40.5 cm²) than Ganada (25.3 cm²). Apparent photosynthetic rates were not significantly different between the populations (Ganada: 12 mumol m⁻² s-1 and P.I. 237110: 10 mumol m⁻² s⁻¹). Dark respiration rates for Ganada were not significantly different (1.4 mumol m⁻² s⁻¹) from those of P.I. 237110 (1.9 mumol m⁻² s⁻¹). P.I. 237110 required 88.9 g of water per 1 g of dry matter than Ganada which required 52.3 g of water.

No description available.

No description available.