Lifespan and growth of Astarte borealis (Bivalvia) from Kandalaksha Gulf, White Sea, Russia

Abstract

Marine bivalves are well known for their impressive lifespans. Like trees, bivalves grow by accretion and record age and size throughout ontogeny in their shell. Bivalves, however, can form growth increments at several different periodicities depending on their local environment. Thus, establishing lifespans and growth rates of marine bivalves requires a proper identification of annual growth increments. Here, we use isotope sclerochronology to decipher the accretionary growth record of modern Astarte borealis from the White Sea, Russia (N 67°05.70′; E 32°40.85′). Unlike winter growth increments observed in many other cold-temperate and boreal bivalve and limpet species, prominent growth increments in A. borealis corresponded to the most negative values in the oxygen isotope (δ 18 O) time series indicating that they formed during summer. Furthermore, summer growth increments do not coincide with the external concentric ridges on the shell making the latter feature an unreliable indicator of age. Similar to many other polar bivalves, A. borealis shows slow growth and long life. The von Bertalanffy growth equation for our sample is H t = 29.39*(1 − e (− 0.11(t−(− 1.86)) ). Lifespans of individuals examined here (n = 18) range from 16 to 48 years. Given its impressive longevity and widespread polar distribution, A. borealis may be a potentially valuable skeletal archive for monitoring environmental conditions in the Arctic Ocean and boreal seas in the face of changing climate.

Reproductive traits and population dynamics of benthic invertebrates indicate episodic recruitment patterns across an Arctic polar front

“…Astarte sp. are known to be slow-growing but long-lived, (A. borealis 48 and 150 years (Torres et al, 2011), (Moss et al, 2018); A. moerchi up to 109 years (Olivier et al, 2020)), while the life span of C. crispatus is suggested to be ~20 years (Nilsen et al, 2006). A chronic failure to recruit could therefore result in an aging population but a considerable amount of time before a population collapse (Dayton et al, 2016;Skazina et al, 2013).…”

“…A chronic failure to recruit could therefore result in an aging population but a considerable amount of time before a population collapse (Dayton et al, 2016;Skazina et al, 2013). Assuming a comparable growth rate to A. borealis in the White Sea, the majority of the A. crenata found above the polar front are in excess of 15 years old (Moss et al, 2018) which suggests, in contrast to populations south of the polar front, that recruitment to this region has been limited, and that variable conditions at the polar front can prevent settlement. However, with long life spans, successful recruitment is only required episodically to maintain populations (Dayton et al, 2019), with offspring either recruited from the local population or crossing the polar front during years of greater Atlantic intrusion into the Barents Sea (Årthun et al, 2012;Neukermans et al, 2018).…”

“…The infaunal bivalve Astarte crenata is also dominant in the Barents Sea and found throughout the Atlantic/Arctic boundary, with regionally high abundances (19 ind. 0.5 m -2 , Cochrane et al, 2009;Figure S2b) and a life span up to ~48 years (Moss et al, 2018). Details of reproduction are poorly understood, but broadly align with A. borealis and A. elliptica, which show mature oocytes up to 200 µm diameter throughout the year, with an underlying seasonal intensity in reproduction, and short pelagic larval stages or direct development (Reed et al, 2021;Von Oertzen, 1972).…”

Age and growth of Astarte borealis (Bivalvia) from the southwestern Baltic Sea using secondary ion mass spectrometry

“…Our Previous work used the traditional micromilling techniques to identify annual growth increments in the shells of Astarte borealis (Schumacher 1817) from the White Sea, Russia, where individuals reach 35.5 mm in length (Moss et al 2018). There, individuals grow relatively slowly, experience growth slow-downs in the summer months that result in annual increment formation, and can live for at least 48 years.…”

“…One impediment to this end is that the size of A. borealis varies throughout its distribution. For example, indviduals from the White Sea (max 35.5 mm length; Moss et al 2018) are typically bigger than those from the Baltic Sea (max 28.7 mm length; Zettler 2002). However, because Baltic Sea A. borealis are smaller than their northern counterparts, traditional micromilling techniques cannot be used to identify the seasonal timing of annual growth increments or evaluate whether the season of slowed growth is similar to A. borealis from the White Sea or more typical of other bivalve and limpet species inhabiting cold-temperate to boreal biogeographic zones.…”