Filtration rates of the invasive pest bivalve Limnoperna fortunei as a function of Size and Temperature

Abstract

Clearance rates of Limnoperna fortunei (Bivalvia) were investigated in laboratory experiments using monocultures of the alga Chlorella vulgaris. Experimental conditions included two mollusc sizes (15 and 23 mm), and three water temperatures (15, 20 and 25°C) covering the normal seasonal range in the lower Parana´river and Rı´o de la Plata estuary. Filtration rates obtained were, for the larger mussels: 9.9, 13.1 and 17.7 ml mg tissue dry weight À1 h À1 at 15, 20 and 25°C, respectively; and for the smaller ones: 17.7, 20.8 and 29.5 ml mg À1 h À1 . Differences between sizes and between temperatures (except 15 vs. 20°C) were statistically significant. In absolute terms larger animals have higher clearance rates, but as a function of body mass smaller individuals feed more actively. Within the range of experimental values used, filtration rates were positively associated with water temperature. These clearance rates (125-350 ml individual À1 h À1 ) are among the highest reported for suspension feeding bivalves, including the invasive species Dreissena polymorpha, D. bugensis and Corbicula fluminea. High filtration rates, associated with the very high densities of this mollusc in the Parana´watershed (up to over 200,000 ind m À2 ) suggest that its environmental impact may be swiftly changing ecological conditions in the areas colonized.

The effect of temperature and body size on filtration rates of Limnoperna fortunei (Bivalvia, Mytilidae) under laboratory conditions

“…Moreover, it is of great ecological relevance given that the golden mussel forms aggregations of thousands of individuals which can deplete the seston in invaded sites. Interestingly, according to the data presented by Sylvester et al (2005), the filtration rates recorded in the present study for L. fortunei were among the highest ever recorded for invasive bivalves (Table 2). The discrepancies between the values obtained in the only three studies that quantified filtration rates in L. fortunei (Von Rückert et al 2004, Sylvester et al 2005 andthe present study) were probably due to the methodological differences, particularly with respect to their experimental design and the type of food (cyanobacteria; Chlorella sp.…”

Physiological response of invasive mussel Limnoperna fortunei (Dunker, 1857) (Bivalvia: Mytilidae) submitted to transport and experimental conditions

“…Based on our results, golden mussel showed tolerance to temperature fluctuation during transport, which suggests that this tolerance could strongly influence its invasiveness ability. In fact, the golden mussel can inhabit a wide range of water temperatures (Sylvester et al, 2005;, and in some localities of Brazil -where the water temperature is not below 15 °C -its populations still successfully spread through new watersheds .…”

Relationship of the Clearance Rate and Nonylphenol Uptake Rate of Three Bivalve Species with Different Size Classes and Temperatures

“…재첩의 작은 개 체구간에 비해 큰 개체구간에서의 온도변화에 따른 여수율이 유의 한 차이를 보이지 않은 것은 개체크기가 클수록 개체 간 변이가 커 지는 경향 때문으로 보이며 기존 연구결과에서도 이 같은 경향을 볼 수 있다 (Sylvester et al, 2005).…”

“…그 동안 많은 연구를 통해 이매패류의 여수율은 실험에 사용된 부유생물의 농도와 종, 측정시간, 용존산소, 실험디자인(유수식, 정 수식)과 생리활동에 영향을 미치는 내인성 요인 등에 의해 결과가 달라 질 수 있음이 밝혀졌다 (Werner and Hollibaugh, 1993;Chung et al, 1999;Riisgard, 2001;Lee and Chung, 2001). Lee and Chung (2001) and Bij, 1990), 수온이 증가함에 따라 이매패류의 여수율도 증가 한다는 많은 연구결과와 일치한다 (Sprung, 1995, Sylvester et al, 2005. 변온동물인 이매패류는 대사과정을 통한 열 발생이 없고 외 부의 열에 의지하므로 저온에서는 생물이 스트레스를 받아 생리활 동에 제약이 생기며 아가미의 섬모운동이 약화되어 여수율이 현격 히 낮아질 수 있다.…”