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The role of waterfowl and fishing gear on zebra mussel larvae dispersal

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The zebra mussel, Dreissena polymorpha (Pallas 1771), is an invasive freshwater species with major negative impacts, promoting changes in ecosystem structure and function and also contributing to economic losses. Navigation has been considered the primary vector of dispersion and little importance has been given to alternative natural (waterbirds) and other human vectors. Using an experimental approach under field conditions, we evaluated and compared zebra mussel dispersal potential by fishing gear (waders and keepnets) versus mallard ducks (Anas platyrhynchos), by examining the adherence and survival rate of zebra mussel larvae on each vector. In addition, we evaluated the survival of zebra mussel larvae under desiccating conditions (i.e., a set of controlled temperatures and relative humidities). Larvae adhered to all types of vectors and survived desiccation under both laboratory and field conditions and thus appear able to be dispersed long distances overland by both ducks and fishing gear. Specifically, on a per-event basis, fishing gear has a higher potential to spread zebra mussel larvae than ducks. Survival was three times higher on human vectors and the number of larvae attached to human vectors was over double of that on the ducks. However, our findings demonstrate that natural vectors, like ducks, can contribute to the transport of zebra mussel larvae at a local scale. Nevertheless, since vectors related to human activity presented a higher potential for transport, it is imperative to continue campaigns to raise the awareness of anglers and boaters as well as continue the implementation of legislation to reduce the risk of zebra mussel dispersal.
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ORIGINAL PAPER
The role of waterfowl and fishing gear on zebra mussel
larvae dispersal
Filipe Banha .Irene Gimeno .Munia Lanao .Vincent Touya .
Concha Dura
´n.Miguel A. Periba
´n
˜ez .Pedro M. Anasta
´cio
Received: 16 June 2014 / Accepted: 30 September 2015 / Published online: 8 October 2015
ÓSpringer International Publishing Switzerland 2015
Abstract The zebra mussel, Dreissena polymorpha
(Pallas 1771), is an invasive freshwater species with
major negative impacts, promoting changes in ecosys-
tem structure and function and also contributing to
economic losses. Navigation has been considered the
primary vector of dispersion and little importance has
been given to alternative natural (waterbirds) and
other human vectors. Using an experimental approach
under field conditions, we evaluated and compared
zebra mussel dispersal potential by fishing gear
(waders and keepnets) versus mallard ducks (Anas
platyrhynchos), by examining the adherence and
survival rate of zebra mussel larvae on each vector.
In addition, we evaluated the survival of zebra mussel
larvae under desiccating conditions (i.e., a set of
controlled temperatures and relative humidities). Lar-
vae adhered to all types of vectors and survived
desiccation under both laboratory and field conditions
and thus appear able to be dispersed long distances
overland by both ducks and fishing gear. Specifically,
on a per-event basis, fishing gear has a higher potential
to spread zebra mussel larvae than ducks. Survival was
three times higher on human vectors and the number of
larvae attached to human vectors was over double of
that on the ducks. However, our findings demonstrate
that natural vectors, like ducks, can contribute to the
transport of zebra mussel larvae at a local scale.
Nevertheless, since vectors related to human activity
F. Banha (&)P. M. Anasta
´cio
Departamento de Paisagem, Ambiente e Ordenamento,
Escola de Cie
ˆncias e Tecnologia, Universidade de E
´vora,
MARE - Marine and Environmental Sciences Centre, Rua
Roma
˜o Ramalho, no. 59, 7000-671 E
´vora, Portugal
e-mail: filipebanha@hotmail.com
P. M. Anasta
´cio
e-mail: anast@uevora.pt
I. Gimeno
Instituto Pirenaico de Ecologı
´a – CSIC,
Av. Montan
˜ana 1005, 50059 Zaragoza, Spain
e-mail: irene.gimeno@ipe.csic.es
M. Lanao
Tragsatec, Paseo Pamplona, 5, 1
a
-2
a
planta,
50004 Zaragoza, Spain
e-mail: mlanao@tragsa.es
V. Touya C. Dura
´n
A
´rea de Calidad de las Aguas, Confederacio
´n
Hidrogra
´fica del Ebro, Paseo Sagasta 24-28,
50071 Zaragoza, Spain
e-mail: vtouya@chebro.es
C. Dura
´n
e-mail: cduran@chebro.es
M. A. Periba
´n
˜ez
Grupo de Investigacio
´n Gobierno de Arago
´n:
Restauracio
´n ecolo
´gica, Departamento de Patologı
´a
Animal, Universidad de Zaragoza, Miguel Servet 177,
50013 Zaragoza, Spain
e-mail: mperilop@unizar.es
123
Biol Invasions (2016) 18:115–125
DOI 10.1007/s10530-015-0995-z
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