Veligers of an introduced bivalve, Limnoperna fortunei,

ESTEBAN M. PAOLUCCI, ERIK V. THUESEN, DANIEL H. CATALDO, AND, DEMETRIO BOLTOVSKOY

FRESHWATER BIOLOGY (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Año: 2010 vol. 55 p. 1831 - 1844

0046-5070

1. Larvae of ‘sa´balo’, Prochilodus lineatus, whose adults represent over 60% of overall fish biomass in the Rý´o de la Plata Catchment, have been observed to feed intensively on veligers of the exotic bivalve Limnoperna fortunei. 2. To assess the effects of this dietary shift on the growth of P. lineatus, 28-day laboratory experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by 2. To assess the effects of this dietary shift on the growth of P. lineatus, 28-day laboratory experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by biomass in the Rý´o de la Plata Catchment, have been observed to feed intensively on veligers of the exotic bivalve Limnoperna fortunei. 2. To assess the effects of this dietary shift on the growth of P. lineatus, 28-day laboratory experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21% for veliger-enriched, natural and low-veliger diets, respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by respectively. Larvae fed a veliger-enriched diet grew to a significantly larger size than larvae fed the other two diets. In energetic balance comparisons using metabolic rates and prey energy content, all three diets were sufficient to support metabolism and growth. The greatest values of excess energy at the end of each week were in the veliger-enriched experiments. 4. Feeding on veligers of L. fortunei significantly enhances the growth of P. lineatus larvae and supports the idea that this new and abundant resource is selectively preyed upon by and supports the idea that this new and abundant resource is selectively preyed upon by experiments were carried out feeding newly hatched P. lineatus larvae with three diets: zooplankton artificially enriched with L. fortunei veligers; natural zooplankton; and zooplankton artificially enriched with cladocerans and copepods. The average length, weight and gut contents of the fish larvae were assessed weekly and metabolic rates of fish larvae were measured. 3. Proportions of veligers in gut contents were always higher than those in the experimental diet: 100, 76 and 21%