Fish and Fish-Leeches on Rocky Shores Around Britain

1995 ◽  
Vol 75 (2) ◽  
pp. 311-322 ◽  
Author(s):  
N.A. Hussain ◽  
E.W. Jones-Knight
Keyword(s):  
The Arctic ◽  
Rocky Shores ◽  
Rock Pools ◽  
Southern Limit ◽  
Cleaner Fish ◽  
South West ◽  
Summer Temperatures ◽  
Myoxocephalus Scorpius

Collecting water from rock pools just above rising tides, usually in winter and spring, yielded 1412 Lipophrys pholis, 255 Pholis gunnellus and 29 Coryphoblennius galerita, bearing respectively 172, 8 and 1 Oceanobdella blennii, 744 Taurulus bubalis bearing six Oceanobdella microstoma and 14 Sanguinothus pinnarum, and a Myoxocephalus scorpius with a single O. microstoma; fishes of 23 other species totalled 1243, but none bore leeches externally. Oceanobdella blennii was found mainly in February and March (some in gill chambers), at temperatures generally below 8°C, with lower numbers (all external) in April and May and none later. Infestation was highest in Northumberland. Leeches on P. gunnellus were smaller than those on L. pholis, which they would not attack. They were confined to Northumberland and Scotland, where L. pholis was scarcer. The southern limit of O. blennii seemed to be in north Cornwall, but O. microstoma, though more stenothermal, extends from the Arctic to south Devon, its hosts living mostly subtidally. It is hidden under the chin of Cottidae, whereas S. pinnarum is easily seen on the fins. Abundance in south-west Britain of the ‘cleaner fish’ Crenilabrus melops may explain why S. pinnarum, though common in Scotland and tolerant of summer temperatures, is scarce in Anglesey and not found further south.

scholarly journals Aspects of the Glaciology of Meighen Island, Northwest Territories, Canada

1965 ◽  
Vol 5 (40) ◽  
pp. 399-410 ◽  
Author(s):  
K. C. Arnold
Keyword(s):  
Snow Accumulation ◽  
The Arctic ◽  
North Coast ◽  
Ice Cap ◽  
The North ◽  
Four Seasons ◽  
Northern Half ◽  
Northern Edge ◽  
Summer Temperatures ◽  
Made In

Abstract Meighen Island lies in the centre of the north coast of the Queen Elizabeth Islands and fronts on the Arctic Ocean. An ice cap of about 76 km.2 covers about one-tenth of the island. Its greatest thickness of 150 m. occurs under the summit, near the south end, which was 268 m. above sea-level in 1960. The northern half of the ice cap is less than 30 m. thick; and the total volume is of the order of 2,000 × 106 m.3. Precipitation is low in the northern Queen Elizabeth Islands, and Meighen Island lies in an area where summer temperatures are lowest. In the winters of 1959–60, 1960–61 and 1961–62, the snow accumulation was 12.6, 18.2 and 14.1 cm. of water equivalent. Some snowfall remained on the higher part of the ice cap in the cold summer of 1961; but the ice cap diminished in volume in each year; by 36 × 106, 72 × 106, 22 × 106 and 91 × 106 m.3 in the 1959, 1960, 1961 and 1962 ablation seasons. If the conditions of these four seasons were maintained the ice cap would disappear in about 100 yr. However, a radio-carbon dating of a saxifrage exposed by the retreat of the ice from a small nunatak near the northern edge gave a date of less than 100 yr., and it appears that the existence of the ice cap might be sensitively related to recent climatic change. Careful surveys were made in 1959, 1960 and 1961 in an attempt to detect movement in the ice cap. Unequivocal evidence is not available from these surveys; but the stake network has been maintained and another survey has recently been completed.

Corrigendum to: Size, depth and position affect the diversity and structure of rock pool communities in an urban estuary

2019 ◽  
Vol 70 (7) ◽  
pp. 1045
Author(s):  
Nina Schaefer ◽  
Katherine A. Dafforn ◽  
Emma L. Johnston ◽  
Mariana Mayer-Pinto
Keyword(s):  
Species Diversity ◽  
Environmental Conditions ◽  
Outer Zone ◽  
Ecological Niches ◽  
Rocky Shores ◽  
Rock Pools ◽  
Rock Pool ◽  
Taxa Richness ◽  
Urban Estuary ◽  
Sydney Harbour

Rock pools provide a range of ecological niches that can support diverse assemblages on rocky shores. As intertidal shores are increasingly lost to developments, understanding the drivers of diversity in rock pools is important for the conservation and construction of these key habitats. In this study we investigated relationships between physical characteristics of rock pools and their biota in an urban estuary. We sampled the biota every 6 weeks for 1 year at sites in the inner and outer zones of Sydney Harbour. In the well-flushed and exposed outer zone, sessile and mobile taxa richness was positively related to rock pool width, whereas only mobile taxa richness was related to depth and volume. In the more urbanised and less exposed inner zone, mobile taxa richness was positively related to rock pool width and volume. In both zones, sessile taxa richness decreased with increasing height on shore. Our results suggest that the biodiversity of intertidal rock pools varies depending on their position in Sydney Harbour and the available species pool. Therefore, restoration efforts should consider rock pool size parameters and local environmental conditions, including location, so designs can be optimised to maximise species diversity in these pools.

scholarly journals Spatio-temporal variability of Arctic summer temperatures over the past 2 millennia

2018 ◽  
Vol 14 (4) ◽  
pp. 527-557 ◽  
Author(s):  
Johannes P. Werner ◽  
Dmitry V. Divine ◽  
Fredrik Charpentier Ljungqvist ◽  
Tine Nilsen ◽  
Pierre Francus
Keyword(s):  
Statistical Testing ◽  
Probabilistic Constraints ◽  
The Arctic ◽  
Reconstruction Technique ◽  
Major Advance ◽  
Proxy Data ◽  
Spatially Resolved ◽  
Recent Warming ◽  
Reconstructed Temperature ◽  
Summer Temperatures

Abstract. In this article, the first spatially resolved and millennium-length summer (June–August) temperature reconstruction over the Arctic and sub-Arctic domain (north of 60° N) is presented. It is based on a set of 44 annually dated temperature-sensitive proxy archives of various types from the revised PAGES2k database supplemented with six new recently updated proxy records. As a major advance, an extension of the Bayesian BARCAST climate field (CF) reconstruction technique provides a means to treat climate archives with dating uncertainties. This results not only in a more precise reconstruction but additionally enables joint probabilistic constraints to be imposed on the chronologies of the used archives. The new seasonal CF reconstruction for the Arctic region can be shown to be skilful for the majority of the terrestrial nodes. The decrease in the proxy data density back in time, however, limits the analyses in the spatial domain to the period after 750 CE, while the spatially averaged reconstruction covers the entire time interval of 1–2002 CE.The centennial to millennial evolution of the reconstructed temperature is in good agreement with a general pattern that was inferred in recent studies for the Arctic and its subregions. In particular, the reconstruction shows a pronounced Medieval Climate Anomaly (MCA; here ca. 920–1060 CE), which was characterised by a sequence of extremely warm decades over the whole domain. The medieval warming was followed by a gradual cooling into the Little Ice Age (LIA), with 1766–1865 CE as the longest centennial-scale cold period, culminating around 1811–1820 CE for most of the target region.In total over 600 independent realisations of the temperature CF were generated. As showcased for local and regional trends and temperature anomalies, operating in a probabilistic framework directly results in comprehensive uncertainty estimates, even for complex analyses. For the presented multi-scale trend analysis, for example, the spread in different paths across the reconstruction ensemble prevents a robust analysis of features at timescales shorter than ca. 30 years. For the spatial reconstruction, the benefit of using the spatially resolved reconstruction ensemble is demonstrated by focusing on the regional expression of the recent warming and the MCA. While our analysis shows that the peak MCA summer temperatures were as high as in the late 20th and early 21st centuries, the spatial coherence of extreme years over the last decades of the reconstruction (1980s onwards) seems unprecedented at least back until 750 CE. However, statistical testing could not provide conclusive support of the contemporary warming to exceed the peak of the MCA in terms of the pan-Arctic mean summer temperatures: the reconstruction cannot be extended reliably past 2002 CE due to lack of proxy data and thus the most recent warming is not captured.

Observations on the ultrastructure of the spermatozoon of two mytilids from the south-west coast of England

1986 ◽  
Vol 66 (2) ◽  
pp. 385-390 ◽  
Author(s):  
A. N. Hodgson ◽  
R. T. F. Bernard
Keyword(s):  
West Coast ◽  
Rocky Shores ◽  
Firm Conclusion ◽  
The South ◽  
Separate Species ◽  
Systematic Status ◽  
South West ◽  
South West Coast

INTRODUCTIONTwo forms of the genus Mytilus, M. edulis L. and M. galloprovincialis Lmk inhabit the rocky shores of Devon and Cornwall (Hepper, 1957). According to Gosling (1984), controversy has existed since 1860 as to whether M. galloprovincialis is a separate species or a subspecies of M. edulis. In a review of the systematic status of M. galloprovincialis, Gosling (1984) analysed the criteria used to identify and classify this form of Mytilus. Gosling did not reach any firm conclusion on the systematic status of these mytilids, but did suggest that the evidence favoured placing M. galloprovincialis as a variety, ecotype or even subspecies of M. edulis.

Antifreeze Proteins in the Arctic Shorthorn Sculpin (Myoxocephalus scorpius)

ARCTIC ◽  
1982 ◽  
Vol 35 (2) ◽  
Author(s):  
Garth L. Fletcher ◽  
Richard F. Addison ◽  
Don Slaughter ◽  
Choy L. Hew
Keyword(s):  
Antifreeze Proteins ◽  
The Arctic ◽  
Shorthorn Sculpin ◽  
Myoxocephalus Scorpius

scholarly journals Spatial-Temporal Characteristics of Arctic Summer Climate Comfort Level in the Context of Regional Tourism Resources from 1979 to 2019

2021 ◽  
Vol 13 (23) ◽  
pp. 13056
Author(s):  
Yutao Huang ◽  
Xuezhen Zhang ◽  
Dan Zhang ◽  
Lijuan Zhang ◽  
Wenshuai Zhang ◽  
...  
Keyword(s):  
Global Warming ◽  
Comfort Level ◽  
The Arctic ◽  
The Past ◽  
Summer Climate ◽  
Regional Tourism ◽  
Tourism Resources ◽  
Summer Temperatures ◽  
Climate Comfort ◽  
Arctic Summer

In the context of global warming, a key scientific question for the sustainable development of the Arctic tourism industry is whether the region’s climate is becoming more suitable for tourism. Based on the ERA5-HEAT (Human thErmAl comforT) dataset from the European Center for Medium-range Weather Forecasts (ECMWF), this study used statistical methods such as climatic tendency rate and RAPS to analyze the spatial-temporal changes in Arctic summer climate comfort zones from 1979 to 2019 and to explore the influence of changes in climate comfort on Arctic tourism. The results showed the following: (1) With the increase in the Arctic summer temperature, the universal thermal climate index (UTCI) rose significantly from 1979 to 2019 at a rate of 0.457 °C/10a. There was an abrupt change in 2001, when the climate comfort changed from “colder” to “cool”, and the climate comfort has remained cool over the past decade (2010–2019). (2) With the increase in Arctic summer temperatures, the area assessed as “comfortable” increased significantly from 1979 to 2019 at a rate of 2.114 × 105 km2/10a. Compared with the comfortable area in the 1980s, the comfortable area increased by 6.353 × 105 km2 over the past 10 years and expanded to high-latitude and high-altitude areas, mainly in Kola Peninsula, Putorana Plateau, and Verkhoyansk Mountains in Russia, as well as the Brooks Mountains in Alaska. (3) With the increase in Arctic summer temperatures, the number of days rated comfortable on 30% of the grid increased significantly from 1979 to 2019 (maximum increase: 31 days). The spatial range of the area with a low level of comfortable days narrowed and the spatial range of the area with a high level of such days expanded. The area with 60–70 comfortable days increased the most (4.57 × 105 km2). The results of this study suggest that global warming exerts a significant influence on the Arctic summer climate comfort level and provides favorable conditions for further development of regional tourism resources.

Size, depth and position affect the diversity and structure of rock pool communities in an urban estuary

2019 ◽  
Vol 70 (7) ◽  
pp. 1034 ◽  
Author(s):  
Nina Schaefer ◽  
Katherine A. Dafforn ◽  
Emma L. Johnston ◽  
Mariana Mayer-Pinto
Keyword(s):  
Species Diversity ◽  
Environmental Conditions ◽  
Outer Zone ◽  
Ecological Niches ◽  
Rocky Shores ◽  
Rock Pools ◽  
Rock Pool ◽  
Taxa Richness ◽  
Urban Estuary ◽  
Sydney Harbour

Rock pools provide a range of ecological niches that can support diverse assemblages on rocky shores. As intertidal shores are increasingly lost to developments, understanding the drivers of diversity in rock pools is important for the conservation and construction of these key habitats. In this study we investigated relationships between physical characteristics of rock pools and their biota in an urban estuary. We sampled the biota every 6 weeks for 1 year at sites in the inner and outer zones of Sydney Harbour. In the well-flushed and exposed outer zone, sessile and mobile taxa richness was positively related to rock pool width, whereas only mobile taxa richness was related to depth and volume. In the more urbanised and less exposed inner zone, mobile taxa richness was positively related to rock pool width and volume. In both zones, sessile taxa richness decreased with increasing height on shore. Our results suggest that the biodiversity of intertidal rock pools varies depending on their position in Sydney Harbour and the available species pool. Therefore, restoration efforts should consider rock pool size parameters and local environmental conditions, including location, so designs can be optimised to maximise species diversity in these pools.

Paracentrotus lividus (Echinodermata: Echinoidea) attachment force and burrowing behavior in rocky shores of SW Portugal*

Zoosymposia ◽  
2012 ◽  
Vol 7 (1) ◽  
pp. 231-240 ◽  
Author(s):  
DAVID JACINTO ◽  
TERESA CRUZ
Keyword(s):  
Sea Urchins ◽  
Paracentrotus Lividus ◽  
Wave Exposure ◽  
Rocky Shores ◽  
Rock Pools ◽  
Test Diameter ◽  
Test Size ◽  
Shallow Subtidal ◽  
Rocky Habitats ◽  
Intertidal Pools

The rock burrowing sea urchin Paracentrotus lividus is a common wave-swept organism that inhabits intertidal rock pools and shallow subtidal temperate shores. Here we present field data on P. lividus attachment force, burrow shape and test diameter measured in different rocky habitats (intertidal pools, low shore intertidal channels and shallow subtidal shores) and in two study sites with different wave-exposure conditions. These data were then analyzed to look for a pos­sible relationship between the size of sea urchins and their attachment force and burrow shape as well as the influence of wave-exposure and habitat in the measured variables. P. lividus test diameter varied among habitats: urchins were smaller in mid-shore intertidal pools and bigger in shallow subtidal shores. We observed in all studied habitats that attachment force was not correlated with test size, while burrow shape index (BSI) was negatively correlated with test size. Results suggest that the attachment force of large and small urchins was similar, but smaller animals occurred in relatively deeper burrows (higher BSI values). Attachment force was positively correlated with BSI, which indicates that burrows may enhance attachment force of P. lividus living in rocky shores by allowing the use of spines as anchorage points and reducing the urchin area exposed to drag forces. Our results partially support the hypothesis that attachment force and BSI might be influenced by local variation in wave-exposure. Higher values for both attachment strength and BSI were measured in intertidal rock pools, the most wave-exposed habitat considered in this study, suggesting that urchins living in such habitat are more able to resist dislodgment by wave-induced forces since they occupy relatively deeper burrows and thusattach more firmly to the substrate. However, neither attachment force nor BSI were higher in the more exposed shore.

scholarly journals Drill-cored rock pools: an effective method of ecological enhancement on artificial structures

2016 ◽  
Vol 67 (1) ◽  
pp. 123 ◽  
Author(s):  
Ally J. Evans ◽  
Louise B. Firth ◽  
Stephen J. Hawkins ◽  
Elisabeth S. Morris ◽  
Harry Goudge ◽  
...  
Keyword(s):  
Species Richness ◽  
Cost Effective ◽  
Design Stage ◽  
Similar Species ◽  
Rocky Shores ◽  
The Novel ◽  
Rock Pools ◽  
Artificial Rock ◽  
Natural Rock ◽  
Habitat Enhancement

Coastal defences are proliferating in response to anticipated climate change and there is increasing need for ecologically sensitive design in their construction. Typically, these structures support lower biodiversity than natural rocky shores. Although several studies have tested habitat enhancement interventions that incorporate novel water-retaining features into coastal defences, there remains a need for additional long-term, fully replicated trials to identify alternative cost-effective designs. We created artificial rock pools of two depths (12cm, 5cm) by drill-coring into a shore-parallel intertidal granite breakwater, to investigate their potential as an intervention for delivering ecological enhancement. After 18 months the artificial rock pools supported greater species richness than adjacent granite rock surfaces on the breakwater, and similar species richness to natural rock pools on nearby rocky shores. Community composition was, however, different between artificial and natural pools. The depth of artificial rock pools did not affect richness or community structure. Although the novel habitats did not support the same communities as natural rock pools, they clearly provided important habitat for several species that were otherwise absent at mid-shore height on the breakwater. These findings reveal the potential of drill-cored rock pools as an affordable and easily replicated means of enhancing biodiversity on a variety of coastal defence structures, both at the design stage and retrospectively.

Intrapopulation Variation of the Esterase-2 Polymorphism in the Serum of Anadromous Arctic Charr, Salvelinus alpinus, from a Northern Labrador River

1988 ◽  
Vol 45 (3) ◽  
pp. 463-468 ◽  
Author(s):  
J. B. Dempson ◽  
E. Verspoor ◽  
J. Hammar
Keyword(s):  
Salvelinus Alpinus ◽  
Arctic Charr ◽  
The Arctic ◽  
Frequency Variation ◽  
Swedish Population ◽  
Intrapopulation Variation ◽  
Stock Discrimination ◽  
Genotype Frequencies ◽  
Summer Temperatures ◽  
Mature Fish

Intrapopulation variation of the diallelic Esterase-2 (serum esterase) polymorphism in the Arctic charr, Salvelinus alpinus, was studied in an anadromous population from the Ikarut River in northern Labrador. Differences in genotype frequencies observed between two sampling years, between sexes, and between juvenile and mature fish were not significant. However, considerable variation was found in the allele frequencies among year-classes. Furthermore, the allele frequency variation was associated with temperature; the frequency of the fast allele, F, was positively correlated with the mean summer temperatures in the year of hatching. The same type of association has been found in a Swedish population. Temperature-dependent selection in late incubation or post-hatching in the fry or fingerling stage could explain the observed association. The nonrandom distribution of the variation within populations has important implications for the use of the polymorphism in stock discrimination work and for the interpretation of interpopulation variation.

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