Whales


Disturbed fertility of male Florida panthers," Baltic grey seals and Baltic ringed seals," common seals,and Beluga whales has been attributed to pollution by PCBs and other organochlorine chemicals. Disturbance of the immunological system of seals by a mechanism involving thymic hormone disruption by PCBs has been suggested as a causative factor in deaths from virus infection. Also, associations between reduced population growth in the European otter and increased tissue levels of PCBs have been demonstrated in the  [c.9]

As with all pollutants, effects of EDs are likely to be greatest when dispersion does not occur and there is consequently an increase in local environmental levels. Endocrine disrupting chemicals that are lipophilic will preferentially bioconcentrate in sediments and biota, thus dispersing only slowly into the wider environment. As previously noted, the aquatic environment is the likely fate of many of these chemicals and certain geographical areas are more susceptible to accumulation, such as areas which accumulate sediment, or locations where dispersion to the wider environment is compromised. Prime examples are estuaries, slow moving sediment-rich rivers, benthic coastal regions and lakes. For example, a nine-year study found that beluga whales in the St. Lawrence estuary have greater body burdens of potential endocrine disrupting chemicals than belugas inhabiting the Arctic Ocean. Other particularly susceptible environments are  [c.79]

Triacylglycerols are rich in highly reduced carbons and thus yield large amounts of energy in the oxidative reactions of metabolism. Complete oxidation of 1 g of triacylglycerols yields about 38 y of energy, whereas proteins and carbohydrates yield only about 17 kj/g. Also, their hydrophobic nature allows them to aggregate in highly anhydrous forms, whereas polysaccharides and proteins are highly hydrated. For these reasons, triacylglycerols are the molecules of choice for energy storage in animals. Body fat (mainly triacylglycerols) also provides good insulation. Whales and Arctic mammals rely on body fat for both insulation and energy reserves.  [c.243]

Large amounts of metabolic water are generated by /3-oxidation (130 HgO per palmitoyl-CoA). For certain animals—including desert animals, such as gerbils, and killer whales (which do not drink seawater)—the oxidation of fatty acids can be a significant source of dietary water. A striking example is the camel (Figure 24.18), whose hump is essentially a large deposit of fat. Metabolism of fatty acids from this store provides needed water (as well as metabolic energy) during periods when drinking water is not available. It might well be said that the ship of the desert sails on its own metabolic water  [c.790]

The most common method of minimizing friction and wear is through lubrication. The first recorded use of a lubricant was in ancient Egypt in 2400 B.c.E. Records show that they would pour a lubricant m front of a sledge being used to move a stone statue, which weighed tens of tons. The lubricant used was probably either water or animal fat. Various lubricants derived from animals and vegetables were used for thousands of years. Some examples of lubricants derived from animals arc sperm oil, whale oil, and lard oil. Sperm oil was taken from a cavity in the head of sperm whales, whale oil from whale blubber, and lard from pig fat. Examples of vegetable lubricants are olive oil, groundnut oil and castor oil.  [c.1164]

There have been moves in the 1990s to replace natural materials of animal origin. This has occurred for humanitarian or economic reasons. One of the first and best known perfume ingredients to be eliminated from use was tincture of ambergris. The starting material for this was ambergris, a principal by-product of the whaling industry. Its use was therefore eliminated as part of international efforts to preserve whale populations. Tincture of ambergris has been replaced by formulas that include the most important contributors to ambergris odor, namely, a-ambrinol [41199-19-3] (59) and dihydro-y-ionone [13720-12-2] (60). These are beheved to form via oxidation and cyclization from the principal component, ambrein [473-03-0] (61) (1).  [c.84]

The declining pod (a small school or herd of marine mammals) of beluga whales in the St. Lawrence river estuary has been the subject of much research. Possible mechanisms for this decline have been recently reviewed. Reproductive abnormalities and immunosuppression have been noted in these animals compared with a pod of Arctic belugas. Histological examination of ovary sections from the St. Lawrence belugas have shown little ongoing ovarian activity. Additionally, an adult beluga from the St. Lawrence has been found to have hermaphroditic characteristics (two ovaries, two testes and the genital tracts of both sexes except for a cervix, vagina and vulva). A complex mixture of contaminants, including organochlorines, is present at high levels in the tissues of the St. Lawrence whales, although the significance of this to the reproductive abnormalities observed is unclear.  [c.66]

Mammals. Exposure to persistent organic compounds has been associated with effects on thyroid hormone levels in mammals. Even at low levels, PCBs have been alleged to suppress thyroid hormone levels in grey seal pups in the Baltic sea. Functional and morphological changes in the thyroid gland have been associated with high body burdens in St. Lawrence beluga whales, " and with phocine distemper infection in harbour seals and harbour porpoises, compared to healthy controls. In otters environmentally exposed to PCBs, there was a strong negative correlation between vitamin A and PCB concentrations, with a high incidence of infectious disease apparent in contaminated animals.  [c.70]

The sex of an organisms may also affect the length of time to which it is exposed to an ED and its bioaccnmillation rate, as well as influencing the effects observed. For example, in Atlantic minke whales, significant differences have been reported in the body burden of E PCB and E DDT in males compared to female or juveniles. " Many studies also have provided evidence of relationships between age or sex and organochlorine body burden in pinnipeds. Male seals accumulate organochlorine compounds throughout their life cycle. In contrast, females only accumulate these compounds until reproductive maturity since, during subsequent seasons of gestation and lactation, part of the mother s body burden is transferred to their offspring as a result of mobilisation from fat tissue in which the accumulated chlorinated organic compounds tend to be stored. However, the transfer of chemicals as a result of lactation may be highly selective. For example, in two species of Arctic seal there were lower concentrations of the higher chlorinated PCBs in the pups than the mother a similar pattern has also been noted in the polar bear, " particularly during times of maternal fasting and lactation. Interestingly, increasing concentrations of PCB s were found in the milk as fasting continued.  [c.76]

Myoglobin is the oxygen-storage protein of muscle. The muscles of diving mammals such as seals and whales are especially rich in this protein, which serves as a store for Og during the animal s prolonged periods underwater. Myoglobin is abundant in skeletal and cardiac muscle of nondiving animals as well. Myoglobin is the cause of the characteristic red color of muscle.  [c.481]

Energy returns in more diversified foraging (energy in food/energy spent in collecting and hunting) varied widely they were barely positive for some types of hunting (particularly for small arboreal animals), high for gathering tubers (up to fortyfold), and veiy high for coastal collecting and hunting of marine species ranging from shellfish to whales. Some foraging societies able to secure high energy returns built permanent dwellings and also channeled the surplus energies into more elaborate tools and remarkable artistic expressions.  [c.622]


See pages that mention the term Whales : [c.448]    [c.47]    [c.238]   
12 Endocrine Disrupting Chemicals (1999) -- [ c.9 ]