Topic
Beluga
About: Beluga is a research topic. Over the lifetime, 597 publications have been published within this topic receiving 12425 citations.
Papers published on a yearly basis
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Papers
TL;DR: Stocks of sturgeons are dramatically decreasing, particularly in Eurasia; the world sturgeon catch was nearly 28,000 t in 1982 and less than 2,000T by 1999 and this decline resulted from overfishing and environmental degradation such as: accumulation of pollutants in sediments, damming of rivers, and restricting water flows, which becomeunfavorable to migration and reproduction.
Abstract: The Acipenseriformes (sturgeon and paddlefish)live in the Northern Hemisphere; half of thesespecies live in Europe, mostly in thePonto-Caspian region, one third in NorthAmerica, and the rest in East Asia and Siberia.They reproduce in freshwater and most of themmigrate to the sea, either living in brackishwater (Caspian, Azov, Black and Baltic Seas) orin full seawater on the oceanic continentalshelf. Most species feed on benthic organisms.Puberty usually occurs late in life (5–30 yearsof age) and adult males and females do notspawn on an annual basis. Adults continue togrow and some species such as the beluga (Huso huso) have reached 100 years of age andmore than 1,000 kg weight. Stocks of sturgeonsare dramatically decreasing, particularly inEurasia; the world sturgeon catch was nearly28,000 t in 1982 and less than 2,000 t by 1999.This decline resulted from overfishing andenvironmental degradation such as: accumulationof pollutants in sediments, damming of rivers,and restricting water flows, which becomeunfavorable to migration and reproduction.Several protective measures have beeninstituted; for example, fishing regulation,habitat restoration, juvenile stocking, and theCITES listing of all sturgeon productsincluding caviar. In addition, sturgeon farmingpresently yields more than 2,000 t per year(equivalent to wild sturgeon landings) andabout 15 t of caviar. Hopefully, thisartificial production will contribute to areduction of fishing pressure and lead to therehabilitation of wild stocks.
504 citations
TL;DR: The exposure of SLE beluga to PAHs and their contamination by these compounds are consistent with the hypothesis thatPAHs are involved in the etiology of cancer in these animals.
Abstract: A population of approximately 650 beluga (Delphinapterus leucas) inhabits a short segment of the St. Lawrence estuary (SLE). Over 17 years (1983-1999), we have examined 129 (or 49%) of 263 SLE beluga carcasses reported stranded. The major primary causes of death were respiratory and gastrointestinal infections with metazoan parasites (22%), cancer (18%), and bacterial, viral, and protozoan infections (17%). We observed cancer in 27% of examined adult animals found dead, a percentage similar to that found in humans. The estimated annual rate (AR) of all cancer types (163/100,000 animals) is much higher than that reported for any other population of cetacean and is similar to that of humans and to that of hospitalized cats and cattle. The AR of cancer of the proximal intestine, a minimum figure of 63 per 100,000 animals, is much higher than that observed in domestic animals and humans, except in sheep in certain parts of the world, where environmental contaminants are believed to be involved in the etiology of this condition. SLE beluga and their environment are contaminated by polycyclic aromatic hydrocarbons (PAHs) produced by the local aluminum smelters. The human population living in proximity of the SLE beluga habitat is affected by rates of cancer higher than those found in people in the rest of Quebec and Canada, and some of these cancers have been epidemiologically related to PAHs. Considered with the above observations, the exposure of SLE beluga to PAHs and their contamination by these compounds are consistent with the hypothesis that PAHs are involved in the etiology of cancer in these animals.
292 citations
TL;DR: Findings suggest that OC contamination is a major factor in the non-recovery of the St. Lawrence beluga population over the last decades.
Abstract: High levels of organochlorine chemicals (OC) were found in the blubber of 26 stranded carcasses of beluga whales from an isolated population in the St. Lawrence Estuary (Quebec, Canada). These compounds accumulated with age in both sexes, being consistently more concentrated in male tissue; high and variable concentrations were found in four juveniles. Lower levels in females are best explained through massive transfer to the newborn during lactation, resulting in juvenile OC concentrations equal to or higher than in adult males. Concentrations in the liver and kidney expressed on a lipid basis suggest dynamic OC exchange between tissues. The adipose tissue concentrations reported here were higher or equal to those found In some pinnipeds, in laboratory animals, and in domestic animals with severe reproductive failure. These findings suggest that OC contamination is a major factor in the non-recovery of the St. Lawrence beluga population over the last decades.
214 citations
TL;DR: Comparison of levels of S-DDT and PCBs in Arctic beluga and ringed seal with those in beluga in the Gulf of St. Lawrence and ringing seal in the Baltic Sea, indicate that overall contamination of the Arctic marine ecosystem is 10-50 times less than the most highly contaminated areas in the northern hemisphere temperate latitude marine environment.
198 citations
TL;DR: The diversity of MP shapes and polymeric identities in beluga points to a complex source scenario, and ultimately raises questions regarding the significance and long-term exposure of this pollutant in this ecologically and culturally valuable species.
170 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 48 |
| 2024 | 74 |
| 2023 | 45 |
| 2022 | 76 |
| 2021 | 30 |
| 2020 | 31 |