Life Sciences Commons^™

Post-Speleogenetic Biogenic Modification Of Gomantong Caves, Sabah, Borneo, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

The Gomantong cave system of eastern Sabah, Malaysia, is well-known as an important site for harvesting edible bird-nests and, more recently, as a tourist attraction. Although the biology of the Gomantong system has been repeatedly studied, very little attention has been given to the geomorphology. Here, we report on the impact of geobiological modification in the development of the modern aspect of the cave, an important but little recognized feature of tropical caves. Basic modeling of the metabolic outputs from bats and birds (CO₂, H₂O, heat) reveals that post-speleogenetic biogenic corrosion can erode bedrock by between …

Bats And Bell Holes: The Microclimatic Impact Of Bat Roosting, Using A Case Study From Runaway Bay Caves, Jamaica, Joyce Lundberg, Donald A. Mcfarlane

WM Keck Science Faculty Papers

The microclimatic effect of bats roosting in bell holes (blind vertical cylindrical cavities in cave roofs) in Runaway Bay Caves, Jamaica, was measured and the potential impact of their metabolism on dissolution modelled. Rock temperature measurements showed that bell holes with bats get significantly hotter than those without bats during bat roosting periods (by an average of 1.1 °C). The relationship is clearest for bell holes with more than about 300 g aggregate bat body mass and for bell holes that are moderately wide and deep, of W:D ratio between 0.8 and 1.6. Measurement of temperature decay after abandonment showed …

A Note On The Thermal Ecology And Foraging Behaviour Of The Egyptian Fruit Bat, Rousettus Aegyptiacus, At Mt. Elgon, Kenya, Donald A. Mcfarlane, Joyce Lundberg

WM Keck Science Faculty Papers

The Egyptian fruit bat, Rousettus aegyptiacus, is an abundant and widely distributed African pteropid (Nowak, 1999). The species is unusual amongst pteropids in being an obligate cave-dweller (Kwiecinski & Griffiths, 1999), sometimes reaching colony sizes in the thousands (Kingdon, 1974). In the caves of Mt. Elgon National Park, western Kenya (1° 08′N, 34° 39′E), precision temperature loggers placed in major Rousettus roosts and intervening passages have allowed us to precisely monitor bat emergence and return times.

The major caves of Mt. Elgon National Park consist of geophagically modified tunnels and collapse chambers cut into Miocene-aged pyroclastic strata (Lundberg & …

Spatial And Temporal Expression Of Vegetation And Atmospheric Variability From Stable Carbon And Nitrogen Isotope Analysis Of Bat Guano In The Southern United States, Christopher M. Wurster, Donald A. Mcfarlane, Michael I. Bird

WM Keck Science Faculty Papers

Stable isotopes of faeces contain information related to the animals feeding ecology. The use of stable isotope values from subfossil faeces as a palaeoenvironmental indicator depends on how faithfully the animal records their local environment. Here we present insectivorous bat guano δ¹³C and δ¹⁵N values from a precipitation gradient across the southern United States and northern Mexico to compare with local vegetation and climate. We find δ¹³C values to be an excellent predictor of expected C₄/CAM vegetation, indicating that the bats are non-selective in their diet. Moreover, we find bat guano δ …

Pollination Biology And Adaptive Radiation Of Agavaceae, With Special Emphasis On The Genus Agave, Martha Rocha, Sara V. Good-Ávila, Fracisco Molina-Freaner, Hector T. Arita, Amanda Castillo, Abisaí García-Mendoza, Arturo Silva-Montellano, Brandon S. Gaut, Valeria Souza, Luis E. Eguiarte

Aliso: A Journal of Systematic and Floristic Botany

Agavaceae are an American family that comprises nine genera and ca. 300 species distributed in arid and semiarid environments, mainly in Mexico. The family is very successful and displays a wide array of ecological, reproductive, and morphological adaptations. Many of its members play important roles as keystone species, because they produce abundant resources during the reproductive season. In this paper we analyze the current knowledge about the pollination ecology of the different genera in the family and the role that pollination systems have played in the ecological and phylogenetic success of the group. After providing an overview of each of …

Guano, Donald A. Mcfarlane

WM Keck Science Faculty Papers

This is an encyclopedia article.

Carbon And Nitrogen Isotopic Signatures Of Bat Guanos As A Record Of Past Environments, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Carbon and nitrogen isotope ratios were measured for various ecogeochemical samples relevant to bat guano ecosystems. In particular, ca. 800-year-old subfossil guano from Jackson's Bay Cave Compex, Jamaica, yielded ratios similar to the modern guano from other Jamaican bat caves but quite different from modern guano of the same area. Diagenetic change and differences in bat food habits were unlikely explanations for the observation. Instead, insects that feed on C4 and CAM plants were the main prey for the bats in present Jackson's Bay area, while the ultimate source of organic matter for bats in other Jamaican caves and for …

Nitrogen And Carbon Isotope Studies Of A Bat Guano Core From Eagle Creek Cave, Arizona, Usa, Hiroshi Mizutani, Donald A. Mcfarlane, Yuko Kabaya

WM Keck Science Faculty Papers

Nitrogen and carbon isotope ratios were studied in a stratified deposit of guano of Mexican Free-tailed bats in Eagle Creek Cave, Arizona, U.S.A. Little diagenetic change was observed over the 25-year time span of the guano deposit. High aridity and reduced circulation of air in the cave are hypothesized to have slowed the normally rapid decomposition of the excreta and the subsequent escape of resultant ammonia. The results suggest the high dependency of the speed of diagenetic change on specific physical and other conditions of the caves and indicate that great care need be exercised in the interpretation of the …

The Prey Of Common Barn Owls (Tyto Alba) In Dry Limestone Scrub Forest Of Southern Jamaica, Donald A. Mcfarlane, Kimball L. Garrett

WM Keck Science Faculty Papers

A collection of common barn-owl (Tyto alba Scopoli) pellets from caves on the Portland Ridge of Jamaica reveals that whereas introduced rodents constitute approximately 90% of the total prey, bats and birds are also frequent prey items. Of the bats, frugivorous species predominate with Ariteus flavescens Gray and Artibeus jamaicensis Leach accounting for the largest portion of the bat prey. Insectivorous bats are markedly under-represented with respect to the known diversity of insectivorous species in the habitat.

Patterns Of Species Co-Occurrence In The Antillean Bat Fauna, Donald A. Mcfarlane

WM Keck Science Faculty Papers

The bat fauna of 25 Antillean islands is presented as a species presence-absence matrix, and used to construct a large population of randomized null-model matrices by Monte-Carlo simulation techniques. Comparison of the observed data matrix with the randomized population reveals a statistically significant departure from randomness which is interpreted as evidence of community structure. The Antillean bat fauna is marked by a pattern of high species co-occurrence, with endemics dominating in the northern Antilles and undifferentiated South American taxa dominating in the southern Antilles. The 'checkerboard' distributions which have been identified in the bird populations of some tropical archipelagos are …

A New Method Of Calculating The Wing Area Of Bats, B.R. Blood, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Wing area is a parameter important to any study of chiropteran flight behaviour (Struthsaker 1961 ; Findley et al. 1972 ; Lawlor 1973), because it is a necessary component for the calculation of aspect ratio and wing loading. Bats possessing high aspect ratio wings usually display swift and steady flight, often at high altitudes. Bats that possess low aspect ratio wings usually display slower, more manouverable flight and often fly at lower altitudes (Findley 1972 ; Findley et al. 1972 ; Mortensen 1977 ; Vaughan 1970). However, despite the importance of wing area, no-one has published a simple, yet accurate, …

An Abbreviated Catalogue Of The Australian Bats In The Collections Of The Natural History Museum Of Los Angeles County, California, Usa., Donald A. Mcfarlane, Kenneth E. Stager

WM Keck Science Faculty Papers

The Natural History Museum of Los Angeles County (LACM) is the repository for some 90,000 mammal specimens of world-wide provenance, and is particularly strong in its collections of Chiroptera. As the result of numerous collecting expeditions undertaken by one of us (KES) since 1954, a substantial representation of Australian bats has been assembled. It is our intent in this paper to bring these collections to the attention of our Australian colleagues, so that this biogeographic and systematic resource might be more widely used.