Optimal Foraging Research Papers - Academia.edu (original) (raw)

The study of parasites and their likely influence on optimal foraging and mate-selection in animals has attracted much attention in recent times. The possible effects of parasites on the host include the manipulation of host behaviour by... more

The study of parasites and their likely influence on optimal foraging and mate-selection in animals has attracted much attention in recent times. The possible effects of parasites on the host include the manipulation of host behaviour by parasites and the emergence of host behavioural adaptations for protecting against parasitism. Self-medication in wild animals is believed to be the behavioural adaptation evolved primarily against parasites and associated diseases. In this article, we have briefly reviewed some types of unusual behaviour observed inmammals, birds and insectswhich can be considered as self-medication.

Increasing diet breadth, a distinguishing characteristic of human foraging strategies at the end of the Pleistocene and in the early Holocene, is known to be a key development contributing to domestication and the spread of agriculture... more

Increasing diet breadth, a distinguishing characteristic of human foraging strategies at the end of the Pleistocene and in the early Holocene, is known to be a key development contributing to domestication and the spread of agriculture and pastoralism. Many scholars have focused on broad-spectrum foraging as a result of resource depression due to demographic stress and/or environmental degradation. However, these factors are absent in an increasing number of cases. New research in the Gobi Desert shows that a dramatic change in organizational strategies, including the intensified use of low-ranked foods from dune-field and wetland habitats, is closely correlated with the establishment of dispersed patches boasting high species diversity and a concentrated abundance of small prey. According to a global suite of paleoenvironmental and archaeological data, it appears that the fragmentation of more homogeneous grassland habitats coincided with the rise of broad-spectrum foraging and that these fragmented ecosystems were ideally suited to the unique set of foraging strategies employed by modern humans. This study shows how broad spectrum foraging, increased human population density, and the shift toward food production should be considered by-products of major environmental changes that created an ecological setting ideal for enhanced human reproduction.

Apex ?1 predators are often threatened with extinction, and reintroduction is one method conservation managers are using to secure their persistence. Yet the ability to predict what these predators will eat upon reintroduction is lacking.... more

Apex ?1 predators are often threatened with extinction, and reintroduction is one method conservation managers are using to secure their persistence. Yet the ability to predict what these predators will eat upon reintroduction is lacking. Here we test predictions of the diet of the lion (Panthera leo), derived from dietary electivity index and optimality theory, using independent data collected from

An ever-growing number of IBMs have been developed by modellers, who aim to aid practitioners and inform a range of issues related to conservation, natural resource management, wildlife management and human socio-economic activities. The... more

An ever-growing number of IBMs have been developed by modellers, who aim to aid practitioners and inform a range of issues related to conservation, natural resource management, wildlife management and human socio-economic activities. The range of practitioners using IBMs to inform their decision-making processes include statutary authorities with responsibilities in environmental and natural resource management, non-governmental organizations such as conservation charities, and those interested in the sustainable use of natural resources. Thanks to advances in computational power, data availability and ecological theory, increasingly complicated, sophisticated IBMs can be produced. Yet this does not mean that these models will be more useful in informing environmental decision-making. IBMs typically require specialist computational knowledge to build and refine the model, and analyse the model outputs, and so practitioners are unlikely to have the requisite skills to use IBMs directly. Conversely, practitioners may have greater knowledge of the system being modelled, so their input into the modelling process is highly desirable. Thus, it is important that modellers and practitioners collaborate effectively to develop models which can address the key questions that practitioners are interested in. In this paper we highlight the uses of IBMs in environmental decision-making, identify potential obstacles to their successful use, and discuss how such obstacles can be overcome. We aim to help practitioners understand the potential benefits of IBMs, and to help modellers to understand how to develop IBMs which will better aid practitioners and inform environmental management and policy. We refer to a coastal bird IBM case study, from which general lessons can be learned.

Este experimento evaluó el efecto de variar el esfuerzo requerido para acceder a alimento sobre la ad- quisición de una respuesta novedosa y sobre las estrategias productor-parásito en grupos de palomas expuestas a un coespecífico... more

Este experimento evaluó el efecto de variar el esfuerzo requerido para acceder a alimento sobre la ad- quisición de una respuesta novedosa y sobre las estrategias productor-parásito en grupos de palomas expuestas a un coespecífico experto. Parvadas de observadores ingenuos fueron expuestos a una palo - ma entrenada en abrir los sellos de depósitos de alimento; el color de los sellos se correlacionó con un esfuerzo diferente; posteriormente, la paloma entrenada fue retirada, manteniéndose la correlación co- lor-esfuerzo. Los resultados mostraron que los observadores adquirieron la respuesta de abrir los se - llos y que la ejecutaron discriminadamente, respondiendo en mayor proporción al color que señaló me - nor esfuerzo; también jugaron papeles tanto de productores como de parásitos, los cuales variaron en función de la composición del grupo. Los datos son congruentes con hallazgos previos sobre aprendi - zaje social y con lo propuesto por la teoría de forrajeo óptimo. Social learni...

Foraging behaviour of bats is supposedly largely influenced by the high costs of flapping flight. Yet our understanding of flight energetics focuses mostly on continuous horizontal forward flight at intermediate speeds. Many bats,... more

Foraging behaviour of bats is supposedly largely influenced by the high costs of flapping flight. Yet our understanding of flight energetics focuses mostly on continuous horizontal forward flight at intermediate speeds. Many bats, however, perform manoeuvring flights at suboptimal speeds when foraging. For example, members of the genus Rhinolophus hunt insects during short sallying flights from a perch. Such flights include many descents and ascents below minimum power speed and are therefore considered energetically more expensive than flying at intermediate speed. To test this idea, we quantified the energy costs of short manoeuvring flights (Rhinolophus species that differ in body mass but have similar wing shapes. First, we hypothesized that, similar to birds, energy costs of short flights should be higher than predicted by an equation derived for bats at intermediate speeds. Second, we predicted that R. mehelyi encounters higher flight costs than R. euryale, because of its higher wing loading. Although wing loading of R. mehelyi was only 20% larger than that of R. euryale, its flight costs (2.61 ± 0.75 W; mean ± 1 SD) exceeded that of R. euryale (1.71 ± 0.37 W) by 50%. Measured flight costs were higher than predicted for R. mehelyi, but not for R. euryale. We conclude that R. mehelyi face elevated energy costs during short manoeuvring flights due to high wing loading and thus may optimize foraging efficiency by energy-conserving perch-hunting.