Predatory mammals

When used to control rodents and predatory mammals in conserved areas, they have caused both primary and secondary poisoning of nontarget species, sometimes associated with population declines. 

Among primates, red-bellied tamarins [Saguinus labiatus) sniff and avoid fecal extracts of jaguar (P. ottw), jaguarundi Herpailurus yagouaroundi), and mar-gay [Feliswiedi) more than those from non-predatory mammals. In this case, it is not clear whether these predators actually prey on tamarins (Caine and Weldon, 1989). 

In the northeastern woodlands of North America coyotes (and originally wolves), gray and red foxes, mustelids, and nowadays feral dogs and cats are the major predatory mammals. (Other important predators such as great homed owls, or hawks, are not considered here, for obvious reasons). Ground-dwelling small... 

Lophirosides (7-10) have weak anti-bacterial activity against Micrococcus luteus (minimum inhibitory amount = 100 pg each), but they may act as defensive substances against predatory mammals on account of their bitterness [17]. 

Diet and proximity to tributyltin affect butyltin concentrations in waterfowl (Kannan et al. 1998a). Seaducks that fed mainly on molluscs had higher concentrations of butyltins than predatory birds feeding on hsh, other birds, and small mammals. Continued exposure of birds to butyltin compounds occurs in harbors and marinas where tributyltin is used on vessels >25 m in length (Kannan et al. 1998a). 

The risk posed to predators eating contaminated fish is determined by comparing the estimated daily intake (EDI) of fish predators (birds or mammals) with the predicted no-effect concentration in these predatory species. If adequate data are missing, the latter value was estimated from laboratory rodent or meat-eating animals (Table 3.3). 

PCB contamination has been observed in the toothed whales iOdontocett) that consume fish, seabird, and other marine mammals. Sperm whales (Physeter macrocephalus, which feed on deepwater squid, have intermediate loads, whereas the predatory dolphins, which feed closer to the surface, carry higher loads. The highest loads have been observed in killer whales (Orcinus orca ), whose diets consists of salmon and seal. In contrast, the baleen whales (Mysttcett) carry much lower loads as their diet is composed of zooplankton. Even whales living in the middle of the ocean fer from land have detectable levels of PCBs and DDT. 

Caine, N. G. and Weldon, P. J. (1989). Responses by red-bellied tamarins Saguinus labiatus) to fecal scents of predatory and non-predatory Neotropical mammals. Biotropica 21, 186-189. 

Soil invertebrates — predatory invertebrates — terrestrial vertebrates —predatory birds or mammals... 

Phytoplankton I Zooplankton Fish eggs and larvae Soft-bottom benthos Hard-bottom benthos Bottom fish Predatory fish Plant life Wetlands and estuaries Amphibians/reptiles Mammals Birds Water quality Human health... 

Considerable attention has been given to the investigation of organochlorine residues in the marine polar ecosystems where the two effects of global distillation and bioaccumulation combine to produce high residues in predatory species such as marine mammals, fish and sea birds. As these compounds preferentially reside in fatty tissues, the high fat content of many of the northern marine species, and the inherited contamination through lactation, indicate that such ecosystems may be some of the most vulnerable. 

The risk assessors conclude that Octa can be considered persistent in the environment but that the available laboratory data indicates a low potential for bioaccumulation. Furthermore, it is concluded that Octa shows no toxicity towards aquatic organisms up to the limit of water solubility, and that effects in other organisms are only observed at relatively high concentrations, based on standard laboratory tests. Nevertheless, the risk assessors note that environmental monitoring of concentrations in biota indicate that Octa, as well as HexaBDE, and HeptaBDE are present at low concentrations in fish, marine mammals and predatory birds eggs. 

Wild animals may be particularly affected by a chemical. For example, DDT had drastic effects on the bird population by influencing the development of eggs (see pp. 92-7) and accumulating to toxic levels in predatory birds. Mammals, by contrast, are not especially affected by the pesticide. In some cases wild animals may be much less sensitive to a chemical for other reasons. For example, frogs are twenty-two times less sensitive to organophosphate insecticides than laboratory mice because the enzyme with which the insecticide reacts is different in the frog. 

This second experiment with predator odors deals with day-active mammals whose behavior can be observed directly and readily. Small mammals snch as sqnirrels are prey to many predatory birds and mammals. Vigilance vis-a-vis predators encompass all major senses smell, vision, and hearing. In the chemical sphere, predators leave signals from scent marks, droppings, and nrine in the environment. Sqnirrels as typical rodents have a keen sense of smell capable of detecting snch predator odors and extracting information snch as how recent the sign is. 

Tongne flicking behavior of snakes in response to odors from small mammals Effects of bait type and location on trapping success with deer mice Food choices of Norway rats Tadpole behavior in the presence of predatory fish... 

Birds, reptiles, amphibians, fish, mammals, and predatory and parasitic insects feed on some pests and help control their numbers. More than half of all insect and insect-like species feed on other insects, some of which are pests. Disease organisms often suppress pest populations. 

Predation Very high, particularly from birds, mammals, and predatory arthropods High, especially when they are at the surface somewhat protected in their burrows Low some predation by ground-dwelling mammals and predatory arthropods... 

North America is home to 15 species of rabbits and hares. All of these are rather abundant within their range. These medium-sized herbivores are important sources of food for many species of predatory birds and mammals, and they are also commonly hunted by people. 

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