Temperature and salinity tolerances of Stage 1 zoeae predict possible range expansion of an introduced portunid crab, Charybdis japonica, in New Zealand

• Published in: Biological invasions 2011-03, Vol.13 (3), p.691-699
• Main Authors: Fowler, Amy E, Gerner, Nadine V, Sewell, Mary A
• Format: Article
• Language: English
• Subjects: Animal populations; Animal reproduction; ballast water; Biomedical and Life Sciences; Charybdis japonica; Chemical analysis; crabs; Crustaceans; Decapoda; Developmental Biology; Ecology; Estuaries; foods; Freshwater & Marine Ecology; geographical distribution; Habitats; Harbors; Hatching; Indigenous species; Introduced species; Invasive species; laboratories; Larvae; Life Sciences; mortality; Nonnative species; Ocean temperature; Original Paper; Plant Sciences; Portunidae; Salinity; salt tolerance; Sea surface temperature; Seawater; surface temperature; surveys; Survival; Swimming; Water analysis; water temperature
• ISSN: 1387-3547; 1573-1464
• DOI: 10.1007/s10530-010-9860-2

The successful invasion of a non-native species depends on several factors, including initial colonization and establishment of a self-sustaining population. Populations of the non-native paddle crab Charybdis japonica were first recognized in the Waitemata Harbour, Auckland, New Zealand in 2000, most likely arriving in ballast waters of an Asian merchant vessel. A survey completed in 2003 found C. japonica throughout the Waitemata Harbour, and further sampling in 2009 has revealed several well established populations in estuaries up to 70 km from the putative invasion point. As the potential for further establishment of C. japonica beyond this area may depend on the temperature and salinity tolerances of their free swimming larvae, we quantified the survival of newly-hatched Stage 1 C. japonica zoeae subjected to temperatures ranging from 11 to 43°C or salinities from 5 to 45‰ in the laboratory. Upon hatching, replicate C. japonica zoeae were directly transferred from 21°C and 34.6‰ seawater to either an experimental temperature or salinity level. Behaviour and death rates of the larvae were monitored over a 24 h period in the absence of food. Comparisons of zoeal survival rates to historical sea surface temperatures and salinities show that C. japonica Stage 1 zoeae tolerate a broad range of temperatures and salinities and could survive natural conditions throughout New Zealand. This gives C. japonica the potential to invade many other New Zealand estuaries and harbours.