Passa al contingut principal

Les invasions bioLògiques en eL medi marí: exemples i impactes a la mediterrània occidental


Biological invasions in marine environment: examples and impacts in the Western mediterranean.
Here, we offer a brief review on the impact invasive species have on coastal marine ecosystems,
with particular focus on the Mediterranean Sea. We also provide a list of the main invasive macroalgal species in the Western Mediterranean, indicating the specific invaded habitats and their
distribution patterns. Although not yet invasive, we describe certain alien invertebrates known to
thrive in several areas of the Spanish Mediterranean. We discuss the main theories on species invasibility and summarize the behaviour of the major Western Mediterranean algal invaders in relation
to these theories. We conclude this discussion by explaining the difficulties involved in predicting
general patterns of invasion, since the success of a given species is dependent not only upon the
existence of predators, competitors and pathogens, nor solely upon resource availability, but also
on other unknown factors that might be critical to properly determine invasive capability. Finally,
we list several methodologies used for the control and/or eradication of marine invasive species,
almost one of which have ever succeeded. It is our belief that prevention remains the most effective measure, as well as the most environmentally friendly and economically viable way to avoid the
introduction of alien species.

Weitzmann, B., Garcia, M., Cebrian, E i Ballesteros, E. (2009)  L'atzavara 18

Comentaris

Entrades populars d'aquest blog

Origin and abundance of beach debris in the Balearic Islands

RESUMEN: ORIGEN Y ABUNDANCIA DE RESIDUOS EN PLAYAS DE LAS ISLAS BALEARES. En un estudio realizado durante el año 2005 se analizó la abundancia, naturaleza y posibles orígenes de los residuos presentes en 32 playas de las Islas Baleares (mar Mediterráneo). La abundancia media de objetos en verano fue de aproximadamente 36 objetos por metro lineal, con un peso correspondiente de 32±25 g por metro lineal, lo cual es comparable a otros estudios en el Mediterráneo. El estudio mediante análisis multivariantes (Análisis de Componentes Principales y Análisis de Redundancia) confirma importantes similitudes entre islas, además de una evolución estacional estadísticamente significante en la composición y abundancia de los residuos. La contaminación durante el verano, expresada en términos de abundancia de objetos en la playa, duplica el valor registrado en invierno. Además, los objetos hallados durante esta época son de naturaleza heterogénea lo que se asocia c...

Autumn Migration of Eleonora’s Falcon Falco eleonorae Tracked by Satellite Telemetry

Falco eleonorae tracked by satellite telemetry. Zoological Studies 48(4): 485-491. The migration route of Eleonora,s Falcon Falco eleonorae has largely been a mystery. To date, the most widely accepted hypothesis on Eleonora,s Falcon’s migration suggested a coastal route through the Mediterranean Sea eastwards, crossing the Suez Canal, and proceeding southwards through the Red Sea following the East coast of Africa to the wintering grounds in Madagascar and the Mascarene Is. This study provides the first description of autumn migration routes of 2 Eleonora,s Falcons (a juvenile male and an adult male) tracked by satellite telemetry from their breeding colonies in the Western Mediterranean to their wintering grounds in southeastern Africa. Contrary to previous suggestions, Eleonora,s Falcons migrated inland across the African continent and did not follow the presumed migration route across the Mediterranean Sea. We discuss the possible origin of this migratory b...

Lizards as pollinators and seed dispersers: an island phenomenon

Although it is well established that many insects, birds and mammals serve as important pollinators and seed dispersers of flowering plants, the role of lizards in these processes has traditionally been considered as rare and less important. However, recent work shows both that their role as mutualistic agents has been underestimated and also reveals a striking pattern – that pollination and seed dispersal by lizards is most common on islands. We argue that this island phenomenon occurs because island lizards reach very high densities (density compensation) and experience a lower predation risk than do those on the mainland and, consequently, can expand their diet to include nectar, pollen and fruit. Although further empirical evidence is needed to confirm this explanation, such relationships could be ideal systems with which to study fundamental ecological problems, such as niche shifts, ecological release and competition. Jens M. Olesen a...