Jakobshavn Glacier, west Greenland, has responded to temperature changes in Ilulissat Icefjord, into which it terminates. This study collected hydrographic observations inside Ilulissat Icefjord and from adjacent Disko Bay between 2001 and 2014. The warmest deep Disko Bay waters were blocked by the entrance sill and did not reach Jakobshavn Glacier. In the fjord basin, the summer mean temperature was 2.88C from 2009 to 2013, excluding 2010, when it was 18C cooler. Despite this variability, summer potential densities in the basin were in the narrow range of 27.20 # s u # 27.31 kg m 23, and basin water properties matched those of Disko Bay in this layer each summer. This relation has likely held since at least 1980. Basin waters from 2009 and 2011-13 were therefore similar to those in 1998/99, when Jakobshavn Glacier began to retreat, while basin waters in 2010 were as cool as in the 1980s. The 2010 basin temperature anomaly was advected into Disko Bay, not produced by local atmospheric variability.This anomaly also shows that Ilulissat Icefjord basin waters were renewed annually or faster. Time series fragments inside the fjord did not capture the 2010 anomaly but show that the basin temperatures varied little subannually, outside of summer. Fjord velocity profiles from summer 2013 implied a basin renewal time scale of about 1 month. In model simulations of the fjord circulation, subglacial discharge from Jakobshavn Glacier could drive renewal of the fjord basin over a single summer, while baroclinic forcing from outside the fjord could not, because of the sill at the mouth.

The completed fruit fly genome was found to contain up to 15 putative UDP-N-acetyl-␣-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase (GalNAc-transferase) genes. Phylogenetic analysis of the putative catalytic domains of the large GalNAc-transferase enzyme families of Drosophila melanogaster (13 available), Caenorhabditis elegans (9 genes), and mammals (12 genes) indicated that distinct subfamilies of orthologous genes are conserved in each species. In support of this hypothesis, we provide evidence that distinctive functional properties of Drosophila and human GalNAc-transferase isoforms were exhibited by evolutionarily conserved members of two subfamilies (dGalNAc-T1 (l(2)35Aa) and GalNAc-T11; dGalNAc-T2 (CG6394) and GalNAc-T7). dGalNAc-T1 and novel human GalNAc-T11 were shown to encode functional GalNActransferases with the same polypeptide acceptor substrate specificity, and dGalNAc-T2 was shown to encode a GalNAc-transferase with similar GalNAc glycopeptide substrate specificity as GalNAc-T7. Previous data suggested that the putative GalNAc-transferase encoded by l(2)35Aa had a lethal phenotype (Flores, C., and Engels, W. (1999) Proc. Natl. Acad. Sci. U. S. A. 96, 2964-2969), and this was substantiated by sequencing of three lethal alleles l(2)35Aa HG8

The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly declined and biomass started to increase, as shown by stock assessments. These positive developments were partly assigned to effective management measures, and the EB cod was considered one of the most successful stock recoveries in recent times. In contrast to this optimistic view, the analytical stock assessment failed in 2014, leaving the present stock status unclear. Deteriorated quality of some basic input data for stock assessment in combination with changes in environmental and ecological conditions has led to an unusual situation for cod in the Baltic Sea, which poses new challenges for stock assessment and management advice. A number of adverse developments such as low nutritional condition and disappearance of larger individuals indicate that the stock is in distress. In this study, we (i) summarize the knowledge of recent changes in cod biology and ecosystem conditions, (ii) describe the subsequent challenges for stock assessment, and (iii) highlight the key questions where answers are urgently needed to understand the present stock status and provide scientifically solid support for cod management in the Baltic Sea.

Round goby Neogobius melanostomus is currently one of the most wide-ranging invasive fish species in Europe and North America. The present study demonstrates how the distribution of round goby has expanded from 2008 to 2013 at a rate of about 30 km yr −1 along the Danish coastline in the western Baltic Sea. Further analyses showed that fish from an established high-density round goby population were slow-growing and displayed poorer condition (weight at age and hepatosomatic index) compared to fish sampled from recently invaded locations (i.e. at the forefront of the distribution range). The established population revealed a broad age distribution and a 1:1 gender ratio, while fish from a recently invaded site were primarily of intermediate ages with a male-biased gender ratio. Otolith analyses suggested that the oldest individuals from the recently invaded area experienced superior growth conditions only in the most recent years, suggesting immigration into the area as adults. Our results suggest that intraspecific competition for food may cause continued dispersal of the species and that population demographics likely relate to invasion history.

Non-indigenous species (NIS) can impact marine biodiversity and ecosystem structure and function. Once introduced into a new region, secondary dispersal is limited by the physiology of the organism in relation to the ambient environment and by complex interactions between a suite of ecological factors such as presence of predators, competitors, and parasites. Early prediction of dispersal potential and future ‘area of impact’ is challenging, but also a great asset in taking appropriate management actions. Aerobic scope (AS) in fish has been linked to various fitness-related parameters, and may be valuable in determining dispersal potential of aquatic invasive species in novel environments. Round goby, Neogobius melanostomus, one of the most wide-ranging invasive fish species in Europe and North America, currently thrives in brackish and fresh water, but its ability to survive in high salinity waters is unknown to date. We show that AS in round goby is reduced by 30% and blood plasma osmolality increased (indicating reduced capacity for osmoregulation) at salinities approaching oceanic conditions, following slow ramping (5 PSU per week) and subsequent long-term acclimation to salinities ranging between 0 and 30 PSU (8 days at final treatment salinities before blood plasma osmolality measurements, 12–20 additional days before respirometry). Survival was also reduced at the highest salinities yet a significant proportion (61%) of the fish survived at 30 PSU. Reduced physiological performance at the highest salinities may affect growth and competitive ability under oceanic conditions, but to what extent reduced AS and osmoregulatory capacity will slow the current 30 km year-1 rate of advance of the species through the steep salinity gradient from the brackish Baltic Sea and into the oceanic North Sea remains speculative. An unintended natural experiment is in progress to test whether the rate of advance slows down. At the current rate of advance the species will reach the oceanic North Sea by 2018/2019, therefore time for taking preventative action is short.