Layered effects of parental condition and larval survival on the recruitment of neighboring haddock stocks

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Friedland, Kevin D., Leaf, Robert T., Kristiansen, Trond, Large, Scott I.
• Other Authors: Bradford, Michael
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2015
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Calanus finmarchicus; Copepods
• Online Access: http://dx.doi.org/10.1139/cjfas-2015-0084; http://www.nrcresearchpress.com/doi/full-xml/10.1139/cjfas-2015-0084; http://www.nrcresearchpress.com/doi/pdf/10.1139/cjfas-2015-0084

We used remote sensing chlorophyll a concentration data, spring copepod abundance, and individual fish condition information to understand the annual recruitment variability of two neighboring haddock (Melanogrammus aeglefinus) stocks in the Gulf of Maine region. When we considered the full range of recruitment variability, the abundance of the copepods Calanus finmarchicus and Pseudocalanus spp. failed to explain the variation in survivor ratio in either stock. However, when we examined this relationship with subsets of the data, we found that Pseudocalanus spp. appears to have had an effect on survivor ratio. The full range of recruitment variability of the Georges Bank stock was found to correlate with the timing and size of the fall bloom the year before recruitment, which has been termed the parental condition hypothesis, suggesting that the fall bloom affects the condition of spawning adults and thus recruitment. The absence of a correlation between fall bloom and recruitment in the Gulf of Maine stock can be attributed to the difference in fall bloom frequency between the two stock areas. It appears that both parental condition and larval survival affect haddock recruitment; however, the relative impact of these effects depends on the contrasting nature of ecosystem environmental drivers.