Preventing The Spread Of Mosquito Fish In Aquatic Ecosystems: Know How?

The new study which is carried out in aquatic ecosystems near urban environments in the provincial area of Barcelona, is approved and signed by the experts Oriol Cano Rocabayera, Adolfo de Sostoa, Lluís Coll and Alberto Maceda, from the Faculty of Biology and the Research Institute of Biodiversity of the University of Barcelona (IRBio).

An exotic species that threatens local fish.

The mosquitofish (Gambusia holbrooki) was brought to Spain in 1921 for the biological control of mosquitoes. It is now comprised in the catalogs of invasive alien species of the Agriculture department, Fisheries and Food and the autonomous communities.

This species is especially present in the south-western areas of the peninsula, the Mediterranean coast and the Ebro basin. In general, it is found in habitats with warm waters, with low or no flow and shallow waters (in general, wetlands and waters). shallow in rivers) and areas with agricultural activity or peri-urban areas affected by pollution. In the peninsular region, it is a competitive hunter which has pushed local species to move, like the Spanish dental carp (Aphanius iberus), the Valencian carp (Valencia hispanica), the Andalusian carp (Aphanius baeticus) and the three-pronged shin. (Gasterosteus aceulatus), apart from other amphibians and invertebrates.

 

Exotic mosquitofish: strategies to survive under adverse conditions

Its high fecundity, sexual precocity, tolerance to environmental pollution and competitive superiority are "reasons which make its monitoring more tough if the only strategies for preserving biodiversity in the water ecosystem are on the basis of the improvement of water or the natural habitat," notes researcher Oriol Cano Rocabayera, first author of the article and member of the Department of Evolutionary Biology, Ecology and Environmental Sciences of the UB and IRBio.

"If some mosquitofish carries a new habitat -or when there are a few of them after a control action for removing the population- this exotic species is able to increase its fecundity rate to balance the population imbalance. However, if the population of mosquitofish is stable and abundant, the fecundity lowers but new mosquitofish are bigger and have more chances of surviving," says Cano.

Modifications in water regime – making of dams, canalizations, etc. -- favor the presence of certain exotic species -- like the mosquitofish -- that prefer water with low flow. The restoration in general of the hydrological regime has the best strategy to control invasive species.

"However, preventing the arrival of these and removing the populations of mosquitofish in the available ecosystems are the most effective actions for their control. Their tiny size, the broad array of tolerance, their diet and links of water ecosystems makes this control and their removal very expensive and difficult."

The new study showcases that habitats with abundant water plants -for example, naturalized dams- and well-preserved environments improve the physical condition of mosquitofish. The complexity of the habitat that’s why is a major factor which brings more preys and shelter against the attack of the predators. "The mosquitofish's survival in high salinity waters is difficult, and these waters are now the natural habitat where the Spanish toothcarp is limited to," comments Cano Rocabayera.

Exotic mosquitofis: strategies to survive in adverse conditions

His researcher, Oriol, points out that Oriol, a researcher from Oriol, stands out for its high fecundity, sexual precocity, tolerance to environmental pollution and competitive superiority. Cano Rocabayera is the first author of the article and member of the Department of Evolutionary Biology, Ecology and Environmental Sciences of the UB and IRBio.

By: Preeti Narula

Content: https://www.sciencedaily.com/releases/2019/05/190524113519.htm