TY - JOUR
T1 - Utilization of the invasive alga Gracilaria vermiculophylla (Ohmi) Papenfuss by the native mud snail Ilyanassa obsoleta (Say)
AU - Guidone, Michele
AU - Newton, Christine
AU - Thornber, Carol S.
PY - 2014/3
Y1 - 2014/3
N2 - The recent invasions of the red alga, Gracilaria vermiculophylla, to the Atlantic and Eastern Pacific Oceans have the potential to significantly alter intertidal and subtidal soft sediment communities. In particular, G. vermiculophylla increases habitat complexity and provides a novel hard substrate in an otherwise two dimensional habitat. Following our observations that the native omnivorous mud snail Ilyanassa obsoleta utilizes G. vermiculophylla for egg capsule deposition, our field surveys demonstrated that the in situ abundance of egg capsules on G. vermiculophylla matched abundances on a native alga Ceramium virgatum and were at least 11-50 times greater than on all other co-occurring macrophytes. Additionally, through mesocosm experiments, we showed that I. obsoleta preferentially deposits eggs on the invasive G. vermiculophylla over native substrates. However, despite the thick layer of egg capsules found on G. vermiculophylla, no detrimental effects were seen on thalli growth. In contrast, growth of the native red alga Ceramium virgatum was significantly reduced when egg capsules were present, suggesting G. vermiculophylla can out-compete native macrophytes in areas of I. obsoleta abundance, while facilitating reproduction of the native mud snail. This novel interaction has the potential to significantly alter biological interactions in soft sediment communities through a variety of different mechanisms, including the alteration of trophic cascades via the increase in mud snail abundance. Furthermore, facilitation of the reproductive success of I. obsoleta may lead to increases in the occurrence of cercarial dermatitis, as I. obsoleta is a known intermediate host organism.
AB - The recent invasions of the red alga, Gracilaria vermiculophylla, to the Atlantic and Eastern Pacific Oceans have the potential to significantly alter intertidal and subtidal soft sediment communities. In particular, G. vermiculophylla increases habitat complexity and provides a novel hard substrate in an otherwise two dimensional habitat. Following our observations that the native omnivorous mud snail Ilyanassa obsoleta utilizes G. vermiculophylla for egg capsule deposition, our field surveys demonstrated that the in situ abundance of egg capsules on G. vermiculophylla matched abundances on a native alga Ceramium virgatum and were at least 11-50 times greater than on all other co-occurring macrophytes. Additionally, through mesocosm experiments, we showed that I. obsoleta preferentially deposits eggs on the invasive G. vermiculophylla over native substrates. However, despite the thick layer of egg capsules found on G. vermiculophylla, no detrimental effects were seen on thalli growth. In contrast, growth of the native red alga Ceramium virgatum was significantly reduced when egg capsules were present, suggesting G. vermiculophylla can out-compete native macrophytes in areas of I. obsoleta abundance, while facilitating reproduction of the native mud snail. This novel interaction has the potential to significantly alter biological interactions in soft sediment communities through a variety of different mechanisms, including the alteration of trophic cascades via the increase in mud snail abundance. Furthermore, facilitation of the reproductive success of I. obsoleta may lead to increases in the occurrence of cercarial dermatitis, as I. obsoleta is a known intermediate host organism.
KW - Gracilaria vermiculophylla
KW - Ilyanassa obsoleta
KW - Invasive macroalga
KW - Mudflat
KW - Narragansett Bay
KW - Substrate preference
UR - http://www.scopus.com/inward/record.url?scp=84892186374&partnerID=8YFLogxK
U2 - 10.1016/j.jembe.2013.12.016
DO - 10.1016/j.jembe.2013.12.016
M3 - Article
AN - SCOPUS:84892186374
SN - 0022-0981
VL - 452
SP - 119
EP - 124
JO - Journal of Experimental Marine Biology and Ecology
JF - Journal of Experimental Marine Biology and Ecology
ER -