In order to understand the reasons as to why this specie is endangered, it is necessary to first know about its physical appearance and biological …show more content…
In the case of A. japonica, the major effect involves the temperature of the water where it habits. The changes in water temperature cause this eel to migrate on a different route and be more exposed to fishery pressures. (P Tatzukawa) Based on this observation, there are many possible outcomes that can cause extinction. For instance, some eels may not return to their original spot because of changes in the water temperature and current hence, gradually they can become a different species. Also, scientists have found that most of these eels’ specie is composed of females. (Han Tzeng) Female eels demonstrated a higher lipid content required for swimming that a vast majority of males lacked. (Limburg A) Based on this information, we can make the connections as to another biological explanation that hinders the eel population. Since the population is mostly composed of females, then the same phenotypic variants would be passed on to other generations. That is, the lipid composition that allows females to survive at a higher rate is absence on the males, hereafter they can’t reproduce. (Limburg. A) If a population is mostly females, then the changes of