For fish with parental care, a nest should meet both the oxygenation needs of the eggs and help protect them against predators. While a small nest opening facilitates the latter, it impedes the former and vice versa. We investigated how the presence of potential egg predators in the form of shore crabs Carcinus maenas affects nest building, egg fanning, defensive displays and filial cannibalism...

The extensive use of pesticides to control agricultural pests poses a serious threat to many non-target organisms of the aquatic environment such as the freshwater crab, B. guerini. The deleterious influence of the pesticide causes physiological, biochemical, histological and such other disorders in the animal exposed. In the present study impact of an organophosphate pesticide, monocrotophos a...

Colour changes in fiddler crabs have long been noted, but a functional interpretation is still lacking. Here we report that neighbouring populations of Uca vomeris in Australia exhibit different degrees of carapace colours, which range from dull mottled to brilliant blue and white. We determined the spectral characteristics of the mud substratum and of the carapace colours of U. vomeris and fou...

Biomedical companies catch and bleed horseshoe crabs for the production of Limulus amebocyte lysate (LAL), a product used for protecting public health (Berkson and Shuster, 1999). LAL is a clotting agent, derived solely from horseshoe crab blood cells, which is used to detect the presence of pathogenic gramnegative bacteria in injectable drugs and implantable medical and dental devices (Mikkels...

Intertidal zone organisms can experience transient freezing temperatures during winter low tides, but their extreme cold tolerance mechanisms are not known. Petrolisthes cinctipes is a temperate mid-high intertidal zone crab species that can experience wintertime habitat temperatures below the freezing point of seawater. We examined how cold tolerance changed during the initial phase of thermal...

To reduce their risk of being eaten, prey may change their morphology or behavior in response to predators, which can result in slower growth and lower fitness. To minimize costs, prey limit anti-predator responses to risky situations, which requires prey to reliably detect cues indicative of predation risk. The purpose of this study was to ascertain how different types of risk cues would affec...

Here we report a unique trophic interaction between the cryptogenic and sometimes highly toxic hydrozoan clinging jellyfish Gonionemus sp. and the spider crab Libinia dubia. We assessed species-specific predation on the Gonionemus medusae by crabs found in eelgrass meadows in Massachusetts, USA. The native spider crab species L. dubia consumed Gonionemus medusae, often enthusiastically, but the...

Responses to innocuous stimuli often habituate with repeated stimulation, but the mechanisms involved in dishabituation are less well studied. Chan et al. (2010b) found that hermit crabs were quicker to perform an anti-predator withdrawal response in the presence of a short-duration white noise relative to a longer noise stimulus. In two experiments, we examined whether this effect could be exp...

a boom in a wild population, although with some unintended consequences: As a way to feed the Soviet Union’s growing northern population, king crabs native to the North Pacific were introduced into the Barents Sea in the 1960s. Now thriving, this population has been welcomed by the fishing industry, as these crabs are a profitable catch. Unfortunately, these crabs are also ravenous omnivores an...

Highly structured nursery habitats promote the survival of juvenile stages of many species by providing foraging opportunities and refuge from predators. Through integrated laboratory and field experiments, we demonstrate that nursery habitat structure affects survival and predator-prey interactions of red king crab Paralithodes camtschaticus. Crabs (<1 yr old [Age 0]; 8 to 10 mm carapace lengt...