Den invasive art, Stillehavsøsters (Crassostrea gigas)ved Agger Tange, Limfjorden: The invasive species, Pacific oyster (Crassostrea gigas) at Agger Tange, Limfjorden

Jens Davids, Mark Holm, Michelle Schollert, Nicolai Herring Rasmussen & Stine Raith Richter

Studenteropgave: Semesterprojekt

Abstrakt

Climate changes and the movement of the climate zones can have great influence on the ecosystems. Introduced species are for instants a huge problem around the world due to the possible damage it can cause on already existing ecosystems. This could be a problem if the introduced specie is invasive and spread to takeover the niche of native species. Due to the resent years with increased water temperature it has been possible for the invasive species Crassostrea gigas to reproduce in the Limfjord in Denmark. Hereby it can threaten the existing ecosystems. The aim with this project is to study the conditions for reproduction of C. gigas in the Limfjord specifically at Agger Tange. And thru field work obtain data by collecting a number of individuals (n= 1140). The main focus has been to make a realistic image of the age distribution of C. gigas at Agger Tange and give an indication of the tendency of the reproduction. In addition discus the biological consequences the presens of C. gigas can have in the Limfjord on the existing ecosystems if the population increases. This discussion will be based on litterateur and related to the results in this project. The conclusion is that an increasing tendency in the reproduction and thereby an increased number of individuals in the population of C. gigas will dominate other species at Agger Tange and possibly the rest of the Limfjord. This could be the case if the continued suitable temperatures for a reproduction will be present. It is still uncertain witch consequences C. gigas can have specifically on an ecosystem like the Limfjord. However it is to assume that a change in the biodiversity will occur.

UddannelserBasis - Naturvidenskabelig Bacheloruddannelse, (Bachelor uddannelse) Basis
SprogDansk
Udgivelsesdato21 jun. 2007
VejledereNiels H. Jensen

Emneord

  • Crassostrea Gigas
  • Agger Tange
  • Limfjorden
  • Invasive arter
  • Transektanalyse