Movement patterns of American eels (Anguilla rostrata) between salt- and freshwater in a coastal watershed, based on otolith microchemistry
Lamson, H.M.; Shiao, J.-C.; Iizuka, Y.; Tzeng, W.-N.; Cairns, D.K. (2006). Movement patterns of American eels (Anguilla rostrata) between salt- and freshwater in a coastal watershed, based on otolith microchemistry. Mar. Biol. (Berl.) 149(6): 1567-1576. http://dx.doi.org/10.1007/s00227-006-0308-2
In: Marine Biology: International Journal on Life in Oceans and Coastal Waters. Springer: Heidelberg; Berlin. ISSN 0025-3162; e-ISSN 1432-1793, more
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Authors | | Top |
- Lamson, H.M.
- Shiao, J.-C.
- Iizuka, Y.
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- Tzeng, W.-N.
- Cairns, D.K.
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Abstract |
Otolith strontium:calcium ratios were used to trace lifetime movements of American eels (Anguilla rostrata) captured in salt-water bays and adjoining freshwater ponds in Prince Edward Island, Canada. Eels were classified into migratory contingents based on their movement patterns. A pond with a pool-and-weir salmonid fishway and a pond drained by a low-gradient channel contained eels that had entered freshwater at all ages, but a pond with a 2.2 m vertical spillway contained only eels that had entered freshwater in the elver year. Salt-water residents were the dominant migratory contingent in salt-water bays (85% of 39), which overturns the paradigm of obligate catadromy for this species. Freshwater residency was the sole pattern found in the pond with the vertical spillway (100% of 12) and the majority contingent in the pond with the low-gradient channel (54% of 24). Inter-habitat shifting was the dominant migratory contingent in eels sampled from the pond with the pool-and-weir fishway (85% of 20). Resident eels were established in salt- and freshwater habitats by the year after their arrival in continental waters. Eels that shifted between habitats increased their rate of inter-habitat shifting with age. The high degree of plasticity in habitat use found in this study is consistent with worldwide Anguillid patterns as revealed by Sr:Ca. |
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