Ephemeral Bio-engineers or Reef-building Polychaetes: How Stable are Aggregations of the Tube Worm Lanice conchilega (Pallas, 1766)?
|Author(s)||Callaway Ruth1, Desroy Nicolas2, Dubois Stanislas3, Fournier Jerome4, Frost Matthew5, Godet Laurent4, Hendrick Vicki J.6, Rabaut Marijn7|
|Affiliation(s)||1 : Swansea Univ, Dept Pure & Appl Ecol, Swansea SA2 8PP, W Glam, Wales.
2 : CRESCO IFREMER, F-35800 Dinard, France.
3 : IFREMER Technopole Brest Iroise, Lab DYNECO Ecol Benth, F-29280 Plouzane, France.
4 : CRESCO MNHN, CNRS, UMR 7208, F-3500 Dinard, France.
5 : Marine Biol Assoc United Kingdom Lab, Plymouth PL1 2PB, Devon, England.
6 : Scottish Marine Inst, Scottish Assoc Marine Sci, Oban Argyll PA37 1QA, Scotland.
7 : Univ Ghent, Dept Biol, Marine Biol Sect, B-9000 Ghent, Belgium.
|Source||Integrative And Comparative Biology (1540-7063) (Oxford Univ Press Inc), 2010-08 , Vol. 50 , N. 2 , P. 237-250|
|WOS© Times Cited||27|
|Abstract||Dense aggregations of tube-worms can stabilize sediments and generate oases for benthic communities that are different and often more diverse and abundant than those of the surroundings. If these features are to qualify as biogenic reefs under nature-conservation legislation such as the EC Habitats Directive, a level of stability and longevity is desirable aside from physical and biological attributes. Lanice conchilega (Pallas, 1766) is widely distributed around the European coast and aggregations of this tube-dwelling polychaete are known to have a positive effect on the biodiversity of associated species in inter- and sub-tidal areas. This increases the value of L. conchilega-rich habitats for higher trophic levels such as birds and fish. However, L. conchilega is currently not recognized as a reef builder primarily due to uncertainty about the stability of their aggregations. We carried out three studies on different spatial and temporal scales to explore a number of properties relating to stability: (1) Individual aggregations of L. conchilega of similar to 1 m(2) were monitored for up to 1 year, (2) records of L. conchilega from a 258-ha area over a 35-year period were analyzed, (3) the recovery of a population of L. conchilega subjected to disturbances by cultivation of Manila clams (Ruditapes philippinarum) was followed over 3 years. The studies provided evidence about the longevity of L. conchilega aggregations, their resistance to disturbance, their resilience in recovering from negative impact and their large-scale persistence. The results showed that populations of L. conchilega were prone to considerable fluctuation and the stability of aggregations depended on environmental factors and on recruitment. The tube-worms proved to be susceptible to disturbance by cultivation of Manila clams but demonstrated the potential to recover from that impact. The long-term monitoring of a large L. conchilega population in the Bay of Mont Saint Michel (France) indicated that aggregations can persist over many decades with a constant, densely populated core area and an expanding and contracting more thinly populated fringe zone. The stability of aggregations of L. conchilega and the structures they form do not unequivocally fit the currently accepted definition of a reef. However, given L. conchilega's accepted reef-like potential to influence diversity and abundance in benthic communities, we suggest clarifying and expanding the definition of reefs so that species with records of significant persistence in particular areas and which otherwise meet expectations of reefs are included within the definition.|