[PAST EVENT] Layered Effects of Parental Condition and Larval Survival on the Recruitment of Haddock Stocks

November 18, 2015
12pm - 1pm
VIMS - Watermen's Hall, Classroom A/B
1375 Greate Road
Gloucester Point, VA 23062Map this location
Fisheries Science Noon Seminar Series

Speaker: Kevin Friedland

Title: Layered Effects of Parental Condition and Larval Survival on the Recruitment of Neighboring Haddock Stocks

Abstract: We used remote sensing chlorophyll-a concentration data, spring copepod abundance, and individual fish condition information to understand the annual 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 stocks. However, when we examined this relationship with subsets of the data, we found that Pseudocalanus spp. appears to have 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 the environmental drivers of the ecosystem.

Bio: Kevin Friedland is a researcher with the National Marine Fisheries Service at the Narragansett Laboratory in Rhode Island, USA. He holds a bachelors degree in ecology from Rutgers College in New Jersey and a doctorate from the College of William and Mary in Virginia. His dissertation research was on the distribution and feeding ecology of Atlantic menhaden. During his professional career, he has done research on menhaden, bluefish, sea herring, sturgeon, eel, cod, haddock, and salmon. His publications cover a range of topics including: estuarine ecology of fishes, functional morphology, feeding ecology, recruitment processes, fisheries oceanography, stock identification, ecosystem ecology, and climate change. His current research is on the effects of growth on the early maturation and survival of Atlantic salmon and the factors controlling the recruitment of cod and haddock. He has served as the chair of several International Council for the Exploration of the Sea (ICES) scientific working groups and is currently the US representative to SCICOM. He is also the chair of the Regional Association for Research on the Gulf of Maine (RARGOM).

[[v|dmk,Professor David Kaplan]]