Thermal behaviour of edible crab Cancer pagurus Linnaeus, 1758 in coastal Norway

Abstract

Ocean warming drives latitudinal shifts in the distribution of ectotherm species. The rate and magnitude of such shifts are constrained by physiology and behavioural thermoregulation. Here, we investigated the thermal preference and lower critical temperature (CTmin) in female edible crab Cancer pagurus, a decapod crustacean with an ongoing northward dispersal along the Norwegian coast. The temperature selected by individual crabs from a northern (latitude ~69°N) and southern (latitude ~62°N) location was examined in a horizontal gradient (5.5-14.5°C) under a simulated day and night light regime. Irrespective of origin, crabs showed pronounced responses to the light cycle – during the day crabs stayed inactive in the warm end of the gradient but during night they actively explored the entire gradient. A preferred temperature of ~13 °C (measured as mode of loggings) was identified for crabs at both locations. Righting reflex experiments of crabs exposed to a rapid temperature drop (7 - 1 °C at -0.1 °C/min) identified a CTmin of ~1.3 °C (i.e., the temperature at which 50% of crabs failed to right from an up-side-down position), and with no significant difference between locations (p > 0.05). Our results provide important information about the functional characteristics of edible crab, and are discussed in context of the biology and ongoing northward dispersal of the species.

Thermal acclimation and habitat-dependent differences in temperature robustness of a crustacean motor circuit

“…The ~30°C wide temperature range in which the rhythm of both species was regular is more extensive than in the two crab species tested previously ( C. borealis and C. pagurus ). In these species, hot crashes occur well below 30°C, and while the cold crash points have never been measured, animals inhabiting waters between 5°C and 14°C show behavioral responses at temperatures close to freezing ( Bakke et al, 2019 ). This aligns well with their approximate temperature and latitude ranges, spanning from Florida to Newfoundland and 2 to 24°C in C. borealis ( Haefner, 1977 ; Stehlik et al, 1991 ; Lewis and Ayers, 2014 ) and northern Norway to Spain (5°C and 21°C, respectively) 1 for C. pagurus ( Bakke et al, 2019 ).…”

“…In these species, hot crashes occur well below 30°C, and while the cold crash points have never been measured, animals inhabiting waters between 5°C and 14°C show behavioral responses at temperatures close to freezing ( Bakke et al, 2019 ). This aligns well with their approximate temperature and latitude ranges, spanning from Florida to Newfoundland and 2 to 24°C in C. borealis ( Haefner, 1977 ; Stehlik et al, 1991 ; Lewis and Ayers, 2014 ) and northern Norway to Spain (5°C and 21°C, respectively) 1 for C. pagurus ( Bakke et al, 2019 ). Moreover, our findings are consistent with previous investigations that determined the critical thermal maximum (CTmax) of C. pagurus and C. maenas by assessing the righting response of crabs ( Cuculescu et al, 1998 ).…”

The Diversity of Trematodes in Myotis Bats (Chiroptera, Vespertilionidae) from the Samarskaya Luka (European Russia)

“…The parasitic worms were then mounted in Canada balsam. Trematode species were identified according to Zdzietowiecki [20,23], Khotenovsky [24], Sharpilo and Iskova [31], Tkach et al [41], and Skrjabin and Antipin [68].…”

Morphological and molecular characterization of plagiorchiid trematodes (Plagiorchis: Plagiorchiidae, Digenea) from bats with redescription of Plagiorchis mordovii Shaldybin, 1958

“…Plagiorchis vespertilionis is a common parasite of bats found in many European countries (Odening 1964; Zdzitowiecki 1970; Matskasi 1967, 1973; Skvortsov 1972; Chiriac and Barbu 1973; Bakke and Mehl 1977; Tkach and Sharpilo 1990; Sharpilo and Tkach 1992; Ricci 1995; Sumer and Yildirimhan 2017, 2018, 2019; Shimalov 2021). In Russia, this species is known from bats in the Astrakhan region (Kurochkin and Kurochkina 1962), the Samara region (Demidova and Vekhnik 2004; Kirillov et al 2012a, 2012b, 2017), Mordovia (Schaldybin 1964; Kirillov et al 2015; Ruchin et al 2016; Kirillova et al 2018, 2023), Karelia (Lebedeva et al 2020), and Kamchatka (Orlovskaya and Dokuchaev 2017).…”