Selected aspects of the life history of desert suckers were examined in four southeastern Arizona streams. Diet, age class structure, reproduction, and habitat use were analyzed from field data obtained from April 1987 through October 1988. Adults fed primarily on plant matter, while fry fed almost exclusively on diatoms. Aging of suckers by scales was not possible and length frequencies were too evenly distributed to determine age class structure. In 1988, ovary and teste development occurred from late January through April, with spawning commencing in May. Suckers primarily used pools with high water flow and significant (∼80%) cover formed by tree limbs, branches, leaves, and other debris. Deterioration or loss of suitable habitat is reducing the range of the sucker due to reductions in and manipulations of surface waters.

No description available.

No description available.

Riparian areas in Arizona have been centers for man's activities such as farming, cattle grazing, recreation, wildlife habitat, water, and cities, since the early 1800's. Representing less than one percent of Arizona's land resource base, riparian areas have received a disproportionately high amount of use and abuse. Public and private awareness of the necessity to preserve and manage riparian areas was aroused in the late 1960's by the Arizona Fish and Game Department and United States Forest Service with a study documenting that clearing of riparian areas was detrimental to wildlife habitats. Since the early 1970's national conferences, studies, and legislation concerning protection, preservation, and management of riparian areas have demonstrated the increasing public interest for riparian areas. Proper management of riparian areas requires land managers to have information on the environmental parameters active in these areas. Riparian areas have been studied since the 1930's, but early studies looked mainly at how to increase water yields from riparian areas through vegetation management. It has only been since the 1970's that studies have been aimed at protection and preservation of riparian areas. This dissertation documents an added effort to broaden the existing knowledge on riparian areas in the southwest. A riparian area bordering Paige Creek in southeastern Arizona was monitored for 24 months. Environmental data (e.g. precipitation, streamflow, watertable levels, soils, soil water status, and vegetation) were collected and analyzed with the objective, to determine if soil moisture content could be used as an indicator of a riparian area in the absence of typical riparian vegetation. Statistical tests indicated soil moisture in the upper 48 inches of soil could not be used to indicate the riparian area. The position of existing riparian vegetation was controlled by the location of the watertable. Unless the location of the free water supply is known, soil moisture readings alone could prove misleading.

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No description available.

No description available.

No description available.

Foraging party and territory size of Heterotermes aureus (Snyder) were investigated on the Santa Rita Experimental Range south of Tucson, Arizona. A comparison of three techniques for delineating territorial extent suggested that the release and recapture of dyed termites was most useful, while agonistic behavior among termites may reflect past as well as current associations. Spatial and temporal patterns of termite attack on baits proved to be unreliable. Data obtained via the release and recapture of dyed termites indicated that most territories encompassed an area of several hundred to thousand square meters. These data sharply contrast with those obtained via spatial and temporal patterns of termite attack, which provided an estimate of 9.2 m² for average territory size. Although agonistic responses were useful for differentiating H. aureus colonies, the lack of this behavior among termites did not necessarily imply a current relationship, as they may have been from subgroups that previously had budded off from each other. These groups may be headed by neotenic reproductives, which were found for the first time under field conditions for this species. Data on foraging party size obtained via a mark-release-recapture technique indicated that many H. aureus colonies contained from ca. 50,000 to 300,000 foragers. However, the validity of these estimates is suspect because several of the assumptions of this technique were not met, i.e., marked individuals did not completely mix in the population, but their numbers tended to be more concentrated near release sites, and colonies may have represented open populations. However, exhaustive trapping data also indicated that colonies may contain tens or hundreds of thousands of foragers. As many as 100,000 foragers in a single colony were removed from fiberboard traps during a 1.5-year period. The average foraging party consisted of 1,456 individuals, of which 8.6% were soldiers.

No description available.