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Explore the use of genetics in investigating misappropriation and misrepresentation of fisheries resources and illegal commerce in fish or fisheries products. Learn about species-specific identification and population-specific identification methods.
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Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 Forensic in this chapter concerns the use of scientific methods to explore evidence of potential criminal acts in cases relevant to fisheries, wildlife, and conservation law enforcement. Specifically, this chapter focus on the use of genetics to investigate: - misappropriation of fisheries resources - misrepresentation of the content of fisheries products - illegal commerce in fish or fisheries products The published literature on these topic is thin, probably because documents in criminal cases are not open to the public.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.2 Species-specific identification To identify the species origin of e.g. a block of frozen fish fillet, forensic scientists need diagnostic genetic markers. Generally, there is no shortage of such markers in the open literature. A number of markers are available and some have been used in various applications, including allozymes, mtDNA, ribosomal DNA, and other nuclear markers. Two typical questions recur in the context of forensic species identification. In both cases,the forensic investigation must be based on baseline information about the species.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.2.1Question 1:Is this a legally taken or traded species? Many species are protected by legislation or regulations because their population levels have become low. Protection will often include a ban on catch (e.g. under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (1973). Whales provide a good case study of a forensic problems of species identification analogous to that for fisheries. Whaling was banned for many whale species by the International Whaling Commission in 1986. However, whale products, often of unknown species origin, have been easily available on the market in all years after. The discrimination between legal and illegal products has been difficult. Baker & Palumbi (1994) purchased a variety of commercial whale products marketed in Japan and Korea. They extracted DNA and sequenced 155-178 base pairs of the mtDNA control region. Sequences of DNA for 16 products of unknown species affinity were aligned and compared with reference sequences for 16 cetacean species, including geographic variants where known.
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics Results from Baker & Palumbi (1994). The whale products of unknown species affinity are shown in boldface typing. A strong case was made that those products were from illegal hunting.
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics 17.2.1Question 2:Is this product what the seller claim? There have been many cases of illegal faking products of exclusive and highly price fish products. For example, large eggs from cheap, common fish species have been marketed as sturgeon roe, or caviar, at very high prices. Some products use seductive marketing names and may obtain higher prices thereby. Not long time ago, the Walleye pollack was the largest whitefish stock i the world, and products that were cheap to produce flooded the world markets in various disguises. Even in Norway, walleye pollack could be found in the supermarkets under the market name "Gold cod", a phantacy name. Usually, however, it is the normally very costly products which are faked.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.3 Population-specific identification In some situations, in which exploitation or human-mediated transfer of a genetic stock of fish is restricetd or prohibited as a conservation measure. In such situations there is need for population-specific identification methods. Fixed allelelic differences among populations, not least in marine species. However, modern population genetics techniques and theory provide powerful tools which often allow discrimination between intraspecific groupings at the population level. Problems involving population-specific identification inclode the four following questions (17.3.1-4).
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics 17.3.1 Question 1:From where did this catch come? It is not uncommon in fisheries management that harvest of some stocks in some species may be banned for periods of time. Such measures are usually implemented for conservation or stock rebuilding reasons. For practical reasons, especially in marine fisheries, managers may not be able to control and monitor catches. By sampling a suspected illegal catch and determining its genetic stock affiliation, it is possible to support or refute a hypothesis of illegal fishery. A case study involving population-specific identification concerns the crab fishery in the Alaska and Bering Sea waters. A fishing boat landed a catch od unusually large Alaskan red king crab (Paralithodes camtchaticus). The size of the crab aroused suspicion that they had been taken in Bristol Bay, a closed area. The captain denied this, saying that the crab had been caught near Adak Island. The authorities seized the catch and let scientists compare a set of allozyme allele frequencies in the catch against baseline data. The catch allozyme allele frequencies matched closely those of the red king crab population of the Bering Sea, an area which was closed at the time of fishing. The captain confessed!
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics Bristol Bay The genetic evidense in the red king crab case convinced the court that the unknown sample was taken in a closed area.
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics 17.3.2 Question 2:Is this a legally transported stock? Moving of fish stocks are in most cases illegal for reasons of risk of disease transfer and for general conservation reasons under the precautionary principle. This applies to many American states and most European countries including Norway. A case study here can be the importation of the Florida largemouth bass (Micropterus salmoides) to certain northen states in USA. This is illegal, but nevertheless very desirable for some people. However, the existence of alleles diagnostic to the Florida sub- species would make discovery quite simple if transfer attempts were made. In a bass fishing tournament in Texas, the apparent winner was suspected of having smuggled in a lage bass from outside the tournament area. Allozyme analyses of tissue samples of the winner fish showed genetic characteristics of the Florida subspecies, and suggested that it had been smuggled into the tournament site. The angler was charged and found guilty of fraud.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.3.3 Question 3: Did somebody illegally sell a licenced stock? This is a type of problem tied to production of fingerlings for growout and commercial sales, product licenses and license stakeholders. At present, the problem is somewhat hypothetical and no examples are given, but it may become reality in future, as the fish farming industry grows and competition hardens. If so, population-specific identification will probably be among the methods for collecting and judging evidence.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.3.4 Question 4: Did somebody illegally release fish? Farmed fish or exotic fish species may escape from captivity and populate natural habitats. This is generally unwanted, but can be accidental. However, intentional release of such fish can also occur for various reasons including insurance fraud. Legal authoroties may need evidence which can support or refute the alleged crime. Here, population-specific identification, peferably unique marks for the populations in question, would provide information for determining the source of the released fish.
Genetic and biologic stock management Hallerman Ch. 17 Forensics BI 3063 J. Mork H08 17.4 Individual-specific identification Of course, in the same way as in humans, animal species can be individually identified by genetic markers. While this may not be relevant for fish today, it is of value in the conservation of highly endangerd species which are pouched for economical reasons. Of course, such "fingerprinting" would only be possible for a relatively few individuals, for example elephants in a reservate or other big mammals in closed areas. It remains to see if applications will occur in conservation of particular marine resources. The collection of individual genetic baseline data for such small populations might be an effective weapon in the war against pouching for elephant and rhinos tasks, tiger skins, and other products which are sold for high prices on an illegal international market. It is also possible, and has been suggested in many fora, that farmed fish from different brood stocks or production facilities should carry unit-specific genetic tags, so that escaped individuals could be tracked back to their origin (to the very net pen which they escaped from). This could be an effective weapon against eco-crime.
Genetic and biologic stock management BI 3063 J. Mork H08 Hallerman Ch. 17 Forensics THE NORWEGIAN RED LIST http://www.artsdatabanken.no/Article.aspx?m=114&amid=1792