Search results for " CONSERVATION"

A mate to die for? A model of conditional monogyny in cannibalistic spiders.

2012

Monogynous males in various species actively limit themselves to mating with a single female in their lifetime. Whereas previous models have considered monogyny as an obligate mating strategy, here we explore the potential of monogyny to evolve as a context-specific (conditional) behavior. Using a state-dependent dynamic game model based on the biology of the cannibalistic spider Argiope bruennichi, we confirm that conditional monogyny can evolve under broad conditions, including an even sex ratio. We predict that males should make a terminal investment when mating with large, virgin females, especially if population density is low and the encounter occurs late in the season. We encourage e…

Ecosystem rescue : when protection is not enough

2015

More than 30 years of studies and conservation on lesser kestrel in Europe: where do we will go from there?

2021

Our ecological knowledge on the lesser kestrel is today wide, but the reasons for the research are many and varied, leading to an unequal representation and coverage of the issues addressed, which in addition can be more or less directly related to the conservation of the species. For these reasons, I decided to review all the work done so far, to identify the strengths and weaknesses of research applied to the conservation of this species.

Informational interactions and the future of cities

1998

Present-day city growth is chiefly the result of new tertiary activities such as financial and producer services, R&D, or business administration. It seems that these activities need to be more spatially concentrated than traditional manufacturing activities. These new trends affect both the structure of cities and the structure of city systems. The specific nature of the new activities concentrated in city centers makes them information intensive. These activities consume human capital, knowledge and hightech capital, which are all rapidly changing inputs; they are based on complex decisionmakingprocesses; this renders them highly information-dependent. Inasmuch as these activities are the…

The size and shape of shells used by hermit crabs: A multivariate analysis of Clibanarius erythropus

2009

Shell attributes such as weight and shape affect the reproduction, growth, predator avoidance and behaviour of several hermit crab species. Although the importance of these attributes has been extensively investigated, it is still difficult to assess the relative role of size and shape. Multivariate techniques allow concise and efficient quantitative analysis of these multidimensional properties, and this paper aims to understand their role in determining patterns of hermit crab shell use. To this end, a multivariate approach based on a combination of size-unconstrained (shape) PCA and RDA ordination was used to model the biometrics of southern Mediterranean Clibanarius erythropus populatio…

Natural Laboratories for Field Observation About Genesis and Landscape Effects of Palaeo-Earthquakes: a Proposal for the Rocca Busambra and Monte Bar…

2018

Earthquakes are phenomena that are still being learned by the scientific community, and poorly known, especially as regards the prevention, by the population. Having a more complete knowledge is a basic step in understanding the vastness and intensity of the destructive phenomenon that involves a great amount of people. The recent earthquakes occurred in Central Italy (L’Aquila and Amatrice earthquakes) are examples that demonstrate the importance of having knowledge about these phenomena to contrast their destructive effects. We present a geological field trip to recognise causes and landscape effects of palaeo-earthquakes recorded in the Mesozoic rock successions outcropping in Sicily. Th…

Sex-Specific Habitat Selection in an Edge Habitat Specialist, the Western Barbastelle Bat

2011

The niche variation hypothesis suggests that a population's ability to react to varying environmental conditions depend on the behavioural variability of its members. However, most studies on bats, including the work on the habitat use of the western barbastelle bat, Barbastella barbastellus, have not considered sex-specific and individual variability. We studied the habitat use of 12 female and five male western barbastelle bats within their home ranges with respect to available habitat types by applying kernel methods and Euclidean distances. Our results indicate individual habitat preferences within and among sexes of this species. Females preferred deciduous forest and linear elements w…

Evaluating the importance of Marine Protected Areas for the conservation of hawksbill turtles Eretmochelys imbricata nesting in the Dominican Republic

2015

Understanding spatial and temporal habitat-use patterns to protect both foraging and breeding grounds of species of concern is crucial for successful conservation. Saona Island in Del Este National Park (DENP), south-eastern Dominican Republic (DR), hosts the only major hawksbill (Eretmochelys imbricata) nesting area in the DR (100 nests yr �1 , SD = 8.4, range = 93�111), with the population having been critically reduced through hunting. We satellite tracked 9 female hawksbill turtles, and present analyses of their core-use areas with respect to Marine Protected Areas (MPAs) in both their internesting and foraging areas. Kernel utilization distribu- tions indicated that during the internes…

Resembling a Viper: Implications of Mimicry for Conservation of the Endangered Smooth Snake

2014

The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co-operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency…

Risk of Local Extinction of Odonata Freshwater Habitat Generalists and Specialists

2014

Understanding the risk of a local extinction in a single population relative to the habitat requirements of a species is important in both theoretical and applied ecology. Local extinction risk depends on several factors, such as habitat requirements, range size of species, and habitat quality. We studied the local extinctions among 31 dragonfly and damselfly species from 1930 to 1975 and from 1995 to 2003 in Central Finland. We tested whether habitat specialists had a higher local extinction rate than generalist species. Approximately 30% of the local dragonfly and damselfly populations were extirpated during the 2 study periods. The size of the geographical range of the species was negati…