Causes of coral reef degradation
No abstract available.
Geology topics
Publications and source records attributed to R.R. Warner.
No abstract available.
Concepts and theory for the design and application of terrestrial reserves is based on our understanding of environmental, ecological, and evolutionary processes responsible for biological diversity and sustainability of terrestrial ecosystems and how humans have influenced these processes. How well this terrestrial -based theory can be applied toward the design and application of reserves in the coastal marine environment depends, in part, on the degree of similarity between these systems. Several marked differences in ecological and evolutionary processes exist between marine and terrestrial ecosystems as ramifications of fundamental differences in their physical environments (i.e., the relative prevalence of air and water) and contemporary patterns of human impacts. Most notably, the great extent and rate of dispersal of nutrients, materials, holoplanktonic organisms, and reproductive propagules of benthic organisms expand scales of connectivity among near-shore communities and ecosystems . Consequently, the "openness" of marine populations, communities, and ecosystems probably has marked influences on their spatial, genetic, and trophic structures and dynamics in ways experienced by only some terrestrial species. Such differences appear to be particularly significant for the kinds of organisms most exploited and targeted for protection in coastal marine ecosystems (fishes and macroinvertebrates). These and other differences imply some unique design criteria and application of reserves in the marine environment. In explaining the implications of these differences for marine reserve design and application, we identify many of the environmental and ecological processes and design criteria necessary for consideration in the development of the analytical approaches developed elsewhere in this Special Issue.
Using ecological criteria as a theoretical framework, we describe the steps involved in designing a network of marine reserves for conservation and fisheries management. Although we describe the case study of the Channel Islands, the approach to marine reserve design may be effective in other regions where traditional management alone does not sustain marine resources. A group of agencies, organizations, and individuals established clear goals for marine reserves in the Channel Islands, including conservation of ecosystem biodiversity, sustainable fisheries, economic viability, natural and cultural heritage, and education. Given the constraints of risk management, experimental design, monitoring, and enforcement, scientists recommended at least one, but no more than four, reserves in each biogeographic region. In general, the percentage of an area to be included in a reserve network depends on the goals. In the Channel Islands, after consideration of both conservation goals and the risk from human threats and natural catastrophes, scientists recommended reserving an area of 30–50% of all representative habitats in each biogeographic region. For most species of concern, except pinnipeds and seabirds, information about distributions, dispersal, and population growth was limited. As an alternative to species distribution information, suitable habitats for species of concern were used to locate potential reserve sites. We used a simulated annealing algorithm to identify potential reserve network scenarios that would represent all habitats within the smallest area possible. The analysis produced an array of potential reserve network scenarios that all met the established goals.
Five races of cottontail rabbits belonging to three species occur in Virginia. One of them, the Mearns cottontail (Sylvilagus floridanus mearnsi), is reported here for the first time. It occurs in six southwestern counties of the state, while the eastern cottontail (S. f. mallurus) occurs in the remainder of the state with the exception of Smith and Fishermans islands off the eastern coast of Cape Charles, where it is replaced by Hitchens cottontail (S. f. hitchensi). The New England cottontail (S. transitionalis) is found on the higher mountain peaks, above 3000 feet, and the swamp rabbit (S. palustris) occurs in the Dismal Swamp region of southeastern Virginia.....The height of the breeding season for the eastern cottontail in Virginia is March and April, but breeding continues through the entire year except in December and January. The average litter size based on embryo counts was 4.7. The sex ratio of 234 specimens from all parts of the state, taken mostly in the December to February period, was 53 males to 47 females. That of a group of 145 rabbits live-trapped at Blacksburg during February and Marchwas 58 males to 42 females. The figures show that males are more active than females during the winter months, and therefore are more easily taken then....In transplanting cottontails from one section of the state to another, it is recommended that only cottontails of the same race as those originally present in the region being restocked be released there....Tularemia is not a common disease among rabbits in Virginia, but the rabbit ticks are often carriers of the disease and may transmit it to rabbits. Rabbit ticks are also found to be carriers of Rocky Mountain fever and American Q. fever. After the ticks drop off the rabbits to hibernate in the ground, which is likely to occur during mid-winter in Virginia, there is relatively little danger of humans contracting tularemia by contact with rabbits. Present laws in Virginia which prohibit rabbit hunting until the opening of the general hunting season, November 15and November 20--west and east of the Blue Ridge Mountains, respectively--protect the licensed hunters to which these regulations apply, but landowners or tenants are still allowed to take rabbits for their own use on their own land at any time. It is recommended that as a public health measure the taking of cottontails be completely prohibited to all until the opening of the general hunting season.