Environmental determinants of larval herring (Clupea harengus) abundance and distribution in the western Baltic Sea

Abstract

The analysis of the abundance and distribution of the early life‐history stages of the western Baltic spring‐spawning herring population, spanning 23 yr, revealed that the abundance of yolk‐sac larvae was strongly spatially structured and significantly more abundant during the optimal temperature window for viable hatch of herring larvae (9°C to 13°C). The percentage of time encompassing this optimal temperature window exhibited a major contraction between 1995 and 2000 that may have contributed to reducing the supply of yolk‐sac larvae and ultimately contributed to reducing recruitment observed after 2000. Temperature also significantly influenced the abundance of preflexion and flexion larvae, defining dome‐shaped responses with maximum abundances observed between 10.27°C and 13.43°C and between 13.68°C and 18.53°C, respectively. The abundances of postflexion stage larvae were greatest at temperatures exceeding 14°C with no apparent decline in abundance at temperatures of up to 20°C. Temperature also played a significant role in influencing the abundance of larvae through its interaction with the abundance of the preceding developmental stage and provided evidence of stage‐specific temperature‐related mortality. There was also evidence of reduced survival during the preflexion–flexion transition in cohorts produced early in the season relative to those cohorts produced later. Although phenologically plastic species such as herring may be able to alter the dates of spawning, thus partially mitigating the effects of increasing rates of spring warming, constriction of the temperature windows for successful hatching and subsequent ontogenetic development may not be so easily mitigated by changes in phenology.

Development stage distribution as a proxy for feeding success and growth for first feeding Norwegian spring spawning herring larvae

“…Nonetheless, the temperature range in Dodson et al . (2019) was much larger (5–20°C) than in the present study (4–8°C). The analyses presented here showed that the effect of zooplankton on the relative stage occurrence is only significant when temperature is above a certain level (>6°C).…”

“…Grey points represent stations with five or less 1d and 2a larvae in total found a greater positive relationship between abundance of yolk-sac larvae and preflexion larvae for western Baltic spring spawning herring at low range of temperatures indicating higher mortality during the transition at higher temperatures. Nonetheless, the temperature range inDodson et al (2019) was much larger (5-20 C) than in the present study (4-8 C). The analyses presented here showed that the effect of zooplankton on the relative stage occurrence is only significant when temperature is above a certain level (>6 C).…”

“…Dodson et al . (2019) found a greater positive relationship between abundance of yolk‐sac larvae and preflexion larvae for western Baltic spring spawning herring at low range of temperatures indicating higher mortality during the transition at higher temperatures. Nonetheless, the temperature range in Dodson et al .…”

Reduced Reproductive Success of Western Baltic Herring (Clupea harengus) as a Response to Warming Winters

“…Therefore, significant export of larvae by current regimes was considered negligible. According to literature on the temperature-dependent duration of yolk consumption (Klinkhardt, 1986) all larvae within a total length range of 5-9 mm were considered hatchlings in the yolk-sac stage (Polte et al, 2017;Dodson et al, 2019). For this study, seasonal shifts of (i) peak hatching and (ii) hatching duration were investigated, based on the occurrence of maximum abundance of yolk-sac larvae and the number of days where yolk-sac larvae could be found in the system.…”

Common trends in recruitment dynamics of north‐east Atlantic fish stocks and their links to environment, ecology and management

“…Temperature affects recruitment success, as shown by case studies in the Baltic Sea (Baumann et al, 2006;Cardinale et al, 2009;Dodson et al, 2018;Köster et al, 2005), Barents Sea (Gjøsaeter & Bogstad, 1998;Ottersen & Loeng, 2000), North Sea stocks (Arnott & Ruxton, 2002;Kempf, Floeter, & Temming, 2009;van der Veer, Pihl, & Bergman, 1990), on Atlantic cod (Kempf et al, 2009;Olsen et al, 2010;Planque & Fox, 1998;Planque & Frédou, 1999) and flatfish stocks (Fox, Planque, & Darby, 2000;Henderson & Seaby, 2005;Nash & Geffen, 2000;Rijnsdorp et al, 1992); mechanistic link through food availability in the North Sea (Beaugrand et al, 2003;Payne et al, 2009)…”