Phenology of <i>Caulerpa taxifolia</i> and temporal dynamics of its epibiontic meiofauna in the port of Malinska (Croatia, northern Adriatic Sea)

Abstract

SUMMARY:The qualitative and quantitative composition of epibiontic meiofauna were studied in the C. taxifolia settlement recently recorded in the Malinska port (Krk Island, northern Adriatic Sea). The samples were taken monthly, from May 1998 till June 1999 covering the complete life cycle of C. taxifolia. In total, 14 meiofaunal taxa were recorded. The meiofauna assemblage was characterized by the dominance of Copepoda (58%), the subdominant position of Nematoda (25%), and the low single participation of other taxa. The results of monthly monitoring indicated a seasonal trend in meiofaunal distribution. The beginning of the summer was a period of a low meiofaunal abundance (139 ind. sample -1 ), and also a start of its exponential increase. The autumn was characterized by a fairly high abundance (~1000-1500 ind. sample -1 ) and moderate variation of the constituent taxa levels. During the winter exponential growth (to about 10000 ind. sample -1 ) and high faunal diversity was detected. In subsequent months meiofaunal abundance reached over 19.000 ind. sample -1 -remaining extremely high until May when C. taxifolia fronds disappeared. The increase of meiofaunal abundance was positively correlated with the increase of the algal frond's length during the summer-autumn period, and with the increasing quantity of sediment particles and detritus accumulated on algal fronds during the C. taxifolia vegetative cycle. This study has shown that C. taxifolia can provide a suitable habitat for numerous benthic invertebrates, although it is known as a species that reduces the benthic biodiversity. -Se estudió la composición cualitativa y cuantitativa de la meiofauna epibionte en la implantación de Caulerpa taxifolia recientemente registrada en el puerto de Malinska (isla de Krk, mar Adriático septentrional). Se tomaron muestras mensuales, desde mayo de 1998 a junio de 1999, cubriendo el ciclo biológi-co completo de C. taxifolia. En total, se registraron 14 táxones de meiofauna. La comunidad de la meiofauna se caracterizó por la dominancia de copépodos (58%), la posición subdominante de los nemátodos (25%) y la participación reducida de los demás grupos. Los resultados del seguimiento mensual indicaron una tendencia estacional en la distribución de la meiofauna. El inicio del verano fue un período de abundancia reducida de la meiofauna (139 ind. muestra -1 ), y también el comienzo de su aumento exponencial. El otoño se caracterizó por una abundancia relativamente elevada (~ 1000-1500 ind. muestra -1 ) y por la variación moderada de los niveles taxonómicos constituyentes. Durante el invierno se detectó un crecimiento exponencial (hasta cerca de 10.000 ind. muestra -1 ) y una elevada diversidad faunística. En los meses siguientes la abundancia de la meiofauna alcanzó unos 19.000 ind. muestra -1 , y siguió muy alta hasta mayo, cuando desaparecieron los frondes de C. taxifolia. El aumento en la abundancia de la meiofauna estuvo correlacionado positivamente con el aumento de la longitud de los frondes algales durante el período de...

Diferencias entre la composición epifítica de <i>Caulerpa taxifolia</i> y la de la fanerógama <i>Zostera capricorni</i> en Botany Bay (NSW, Australia)

“…Kendrick et al, 1988;Kendrick and Burt, 1997). Our results are in agreement with previous research in the Mediterranean that reports the existence of significant differences in the animal composition between C. taxifolia and control locations (Relini et al, 1998;Travizi and Zavodnik, 2004), and with seasonal variability in the abundance of epiphytic algae (Verlaque and Fritayre, 1994).…”

“…Roberts and Ormond, 1987;Hull 1997;Gratwicke and Speight, 2005;Hereu et al, 2005), including invasive habitat forming species (reviewed by Crooks, 2002). In the Mediterranean, invasive strains of C. taxifolia have been shown to host greater numbers of epiphytic fauna than the native seagrass Cymodocea nodosa (Relini et al, 1998) and to provide shelter to larger proportions of juvenile fish (Francour et al, 1995;Harmelin-Vivien et al, 1996) and meiofauna assemblages than control sites (Travizi and Zavodnik, 2004). In Quibray Bay, epifauna composition during the study period accounted for more of the dissimilarities between C. taxifolia and Z. capricorni than epiphytic algae (36.1% vs. 23.1% respectively), but the total numbers of taxa were not affected.…”