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During the Middle to Upper Paleolithic transition in the Balkan, Italian and Iberian peninsulas of southern Europe, late Neanderthal and early Anatomically Modern Human (AMH) populations may have overlapped in some capacity. Many of the hypotheses and models for the transition interval suggest that Neanderthal populations remained in, or migrated to, refugial zones while AMHs colonized areas not suitable for, or abandoned by, Neanderthals. However, many hypotheses and models have not been conclusively tested due to general issues impeding a clear understanding of the relevant archeological record and because of a lack of specificity in defining and applying the term ‘refugium’. This paper briefly summarizes what is known about the Middle to Upper Paleolithic transition in southern European Peninsulas and discusses some new directions in the use of refugium concepts in the study of Neanderthal extinction and AMH dispersal. We highlight the complexity of the archeological record in each region and in the studies of refugia more generally. Finally, we make an appeal for generating local, multi‐proxy paleoenvironmental and paleoclimatic records to address these complexities so that hypotheses and models integrating refugial concepts in explanations of the Middle to Upper Paleolithic transition can be properly formulated and tested. © 2021 The Authors. Journal of Quaternary Science Published by John Wiley & Sons Ltd. info:eu-repo/semantics/publishedVersion

Ralph and Myrtle Mae Borsodi, two early twentieth century back-to-the-land writers based in rural New York state, wrote the rural agrarian smallholding as a kind of refugium, a philosophical and physical site for those self-sufficient smallholders to survive, even thrive, through an expected US cultural extinction. The centre of their back-to-the-land agrarian refugium is the heterocouple complete with attached gendered roles and expectations. For this self-sufficiency promoting couple, the rural back-to-the-land homestead was the future of a new and better America made up of decentralised, self-sufficient farms and workshops run by those Ralph termed 'quality-minded men'. Indeed, both in their writings and in real life, their self-sufficiency rested on the backs of urban factory workers, the poor and, most likely, people of colour - domestic labourers. Such exploitation was not incidental, but a key component of the ideal world imagined by this couple.

Heterospecific pollen transfer by insect pollinators has the potential to drive inter-species competition between flowering plants. This phenomenon may newly arise in a region if insect pollinator or flowering plant populations change. An agent-based simulation is presented to assess the potential impact of heterospecific pollen transfer by insects on two co-flowering plant species within an environment consisting of a shared central region and species-specific refugia. Where heterospecific pollen asymmetrically suppressed the reproduction of one competitor, the pollen recipient was rapidly ousted from shared regions. If pollinators made deep, repeated, forays into and out of plant refugia, the clogged species was even unseated from its own refugium. When heterospecific pollen symmetrically suppressed plant reproduction, the same effects were observed, but with one or the other species excluded at random by the pollen clogging mediated interaction. We conclude that both symmetrical and asymmetrical heterospecific pollen transfer may be important elements of inter-species dynamics. In particular, our simulation shows pollen and pollinator visits lost to heterospecific flowers may not always be wasted from the producer’s standpoint. Instead, heterospecific pollen delivery may convey a competitive advantage even when the recipient has a refuge safe from direct invasion. This is possible because the pollen producer may use pollinators to clog a competitor’s stigmas in a refugium without entering into competition there for space, nutrients, light, pollinators, or other resources. Consequently, the evolution of plant signals to promote pollinator constancy may not be the only effective strategy in inter-species competition.

Forests create harbour different soil mite communities due to their high spatial heterogeneity, within which microhabitats become biodiversity hotspots or refugia. This study aimed to characterize ...

The contact zones of the distribution ranges of closely related reptile taxa are the source of valuable data on the microevolutionary processes in populations, the history of regional faunas origin, and the environmental preferences of the studied forms. Our study is focused on the genetic structure of the populations of sand lizard, Lacerta agilis Linnaeus, 1758, at the Crimean peninsula. This lacertid species inhabits the mountain (afforested) and plain (steppe) parts of the Crimea, being abundant or common in many areas. Lacerta agilis is represented in the Crimea by two subspecies: the widely distributed Eastern (L. a. exigua Eichwald, 1831) inhabiting a large part of Northern Eurasia, and the endemic (L. a. tauridica Suchow, 1927) residing in the Crimean mountains. Mitochondrial haplogroup affiliation corresponding to one of the subspecies (L. a. tauridica, L. a. exigua or L. a. chersonensis) was established for 225 L. agilis individuals from 81 localities in the Crimea and adjacent mainland territories. The nucleotide sequences of the complete cytochrome b gene of mitochondrial DNA (1143 bp) were studied in 75 L. agilis individuals from 68 localities. The genetic distance between both subspecies inhabiting the Crimea revealed by used molecular marker comprised 2.8%, which indicates their early divergence approximately at the transition of Early to Middle Pleistocene (ca. 1 Mya). L. a. tauridica is characterized by a comparatively deep genetic structure. Haplotypes occupying isolated positions on the phylogenetic tree of this subspecies were found in the south-western part of the Crimean Mountains, what might be explained by the localization of L. agilis microrefugia in areas least affected by the Late Pleistocene cooling. Genetic structure of L. a. exigua is more homogeneous. Another important result of our study was an identification of zones of haplogroups «exigua» and «tauridica» coexistence localized along the northern and eastern margins of the Crimean Mountains. The portion of the «exigua» haplogroup in local populations decreases southward and westward. The observed pattern of the spatial distribution of haplogroups seems to be a result of the hybridization zone formation between the sand lizard subspecies during the Holocene expansion of L. a. exigua. Ecological niches modeling for L. agilis subspecies and analysis of morphological variability of the lizards support the hypothesis of L. a. exigua and L. a. tauridica hybridization in the area of contact of their ranges in the eastern part of the Crimean Mountains.

The riparian forest is one of the most diverse environments of the La Plata River plains. It is represented by patches of humid forests, which are a valuable source of ecosystem services and have recreational and educational potential. However, the riparian forest has undergone constant modification, worsened by private real-estate developments and a lack of government regulation. Among the reserves that protect the riparian forest, The Municipal Ecological Reserve of Avellaneda is the closest to the southern limit of the Autonomous City of Buenos Aires. Although there are around 300 species of wild fauna and flora informally registered in the area, there are only a few studies published about its biodiversity. In this work, the diversity of thirteen native and exotic ferns in the core area (Eco Área) of the reserve is characterized, the origin of the species is also evaluated and comparisons are made with other nearby protected areas. The Eco Área of the Reserve plays an important role as part of the urban reserve corridor of the La Plata River plains and constitutes a refuge for both native and exotic ruderal species. The present work represents the basis for future studies about the population dynamics and the colonization strategies of the ferns.

Animals are known to regulate the composition of their cell membranes to maintain key biophysical properties in response to changes in temperature. For deep-sea marine organisms, high hydrostatic pressure represents an additional, yet much more poorly understood, perturbant of cell membrane structure. Previous studies in fish and marine microbes have reported correlations with temperature and depth of membrane-fluidizing lipid components, such as polyunsaturated fatty acids. Because little has been done to isolate the separate effects of temperature and pressure on the lipid pool, it is still not understood whether these two environmental factors elicit independent or overlapping biochemical adaptive responses. Here, we use the taxonomic and habitat diversity of the phylum Ctenophora to test whether distinct low-temperature and high-pressure signatures can be detected in fatty acid profiles. We measured the fatty acid composition of 105 individual ctenophores, representing 21 species, from deep and shallow Arctic, temperate, and tropical sampling locales (sea surface temperature, −2° to 28°C). In tropical and temperate regions, remotely operated submersibles (ROVs) enabled sampling down to 4000 m. We found that among specimens with body temperatures 7.5°C or colder, depth predicted fatty acid unsaturation levels. In contrast, in the upper 200 m of the water column, temperature predicted fatty acid chain lengths. Taken together, our findings suggest that lipid metabolism may be specialized with respect to multiple physical variables in diverse marine environments. Largely distinct modes of adaptation to depth and cold imply that polar marine invertebrates may not find a ready refugium from climate change in the deep., Summary: Global sampling of comb jellies reveals distinct fatty acid compositions in cold versus deep habitats, suggesting that high hydrostatic pressure requires specialized adaptation of lipid membranes.

Lysogens are common at high bacterial densities, an observation that contrasts with the prevailing view of lysogeny as a low-density refugium strategy. Here, we review the mechanisms regulating lysogeny in complex communities and show that the additive effects of coinfections, diversity and host energic status yield a bimodal distribution of lysogeny as a function of microbial densities. At high cell densities (above 106 cells ml-1 or g-1 ) and low diversity, coinfections by two or more phages are frequent and excess energy availability stimulates inefficient metabolism. Both mechanisms favour phage integration and characterize the Piggyback-the-Winner dynamic. At low densities (below 105 cells ml-1 or g-1 ), starvation represses lytic genes and extends the time window for lysogenic commitment, resulting in a higher frequency of coinfections that cause integration. This pattern follows the predictions of the refugium hypothesis. At intermediary densities (between 105 and 106 cells ml-1 or g-1 ), encounter rates and efficient energy metabolism favour lysis. This may involve Kill-the-Winner lytic dynamics and induction. Based on these three regimes, we propose a framework wherein phage integration occurs more frequently at both ends of the host density gradient, with distinct underlying molecular mechanisms (coinfections and host metabolism) dominating at each extreme.

Alberto Giacometti moved into the studio at 49 Rue Hippolyte-Maindron in 1927, and worked there until the end of his life in 1967.

It is a broadly observed pattern that the non-recombining regions of sex-limited chromosomes (Y and W) accumulate more repeats than the rest of the genome, even in species like birds with a low genome-wide repeat content. Here, we show that in birds with highly heteromorphic sex chromosomes, the W chromosome has a transposable element (TE) density of greater than 55% compared to the genome-wide density of less than 10%, and contains over half of all full-length (thus potentially active) endogenous retroviruses (ERVs) of the entire genome. Using RNA-seq and protein mass spectrometry data, we were able to detect signatures of female-specific ERV expression. We hypothesize that the avian W chromosome acts as a refugium for active ERVs, probably leading to female-biased mutational load that may influence female physiology similar to the ‘toxic-Y’ effect in Drosophila males. Furthermore, Haldane's rule predicts that the heterogametic sex has reduced fertility in hybrids. We propose that the excess of W-linked active ERVs over the rest of the genome may be an additional explanatory variable for Haldane's rule, with consequences for genetic incompatibilities between species through TE/repressor mismatches in hybrids. Together, our results suggest that the sequence content of female-specific W chromosomes can have effects far beyond sex determination and gene dosage. This article is part of the theme issue ‘Challenging the paradigm in sex chromosome evolution: empirical and theoretical insights with a focus on vertebrates (Part II)’.

While coral larval exchange among reef patches is crucial to the persistence of coral metapopulations, larval retention within patches is critical for local population maintenance. In isolated systems such as the Flower Garden Banks (FGB) of the northwest Gulf of Mexico (NW GoM), local retention is thought to play an important role in maintaining high levels of coral cover. Numerous mesoscale cyclonic and anticyclonic features (eddies) are known to spin off from the GoM’s Loop Current, many of which pass over the FGB. We developed a biophysical model of coral larval dispersal (2004–2018) to investigate the extent to which eddies may facilitate coral larval exchange between and within the east and west FGB. Virtual larvae of the broadcast spawning Orbicella faveolata and the brooding Porites astreoides were released and tracked with species-specific reproductive and larval behaviors to investigate differences in retention and connectivity in corals with contrasting life histories. Eddies were detected and tracked using sea surface altimetry and compared with larval trajectories to assess the retentive characteristics of these features. Results suggest consistently high, but species-specific, levels of local retention and cross-bank connectivity in both coral species. High local retention is possible early in the dispersal of P. astreoides, and both species routinely experience retention due to recirculation in eddy features as late as 30 days after planulation or spawning. Eddies passing over the FGB were associated with pulses of between- and within-bank retention, indicating that larvae are capable of dispersing from and returning to coral reefs in the NW GoM. Although opportunities for retention are inherently ephemeral and stochastic due to the nature of Loop Current Eddy (LCE) shedding, eddy propagation should serve as a reliable reseeding mechanism for FGB coral populations. In particular, peaks in late summer eddy propagation correspond with mass coral spawning and may enhance larval retention. These findings support the assertions that healthy FGB reefs may be largely self-sustaining, and that persistent, self-sustaining populations at the FGB may supply downstream reefs with larvae and behave as a remote climate change refugium.

On the basis of many years of research (1972-2019), the peculiarities of the formation of “cold” wintering of near-water and waterfowl in the source and upper reaches of the Angara river are considered. Despite the fact that it has been for a very long time studied, this issue has not yet received proper coverage in the scientific literature. Until now, there are different opinions about the reasons for its formation - sometimes very controversial, which requires a more complete analysis of the available materials. We found out that the formation of wintering is associated with delays in the departure of birds that have not accumulated a sufficient amount of plastic substances necessary for the continuation of migration. Late freezing source and upper course of the Angara river (mid-January - early February) allow birds to stay for a long time. Here, due to the huge mass of water heated in summer, which increases the temperature of the surface air layer in the late autumn and early winter periods, a thermal is refugium formed. However, by the time the birds are able to continue their migration, it becomes impossible. Permanent snow cover and very low air temperatures are in the surrounding areas established, and all lake systems freeze. This thermal refugium, into which birds, delayed with flight, gradually move, becomes an ecological trap, and the “cold” wintering itself is forced.

From the time of Olshausen, Czerny and especially Leopold, ventrofixatin uteri has been exhibited as an ultimum refugium for the treatment of retroflexions.The author says that more than a year ago he expressed his opinion regarding the indications for this operation in the Berlin obstetric society, namely: 1) in cases where, due to other reasons, laparotomy is required with the simultaneous existence of retroflexio - you need to come to the lower mobilis or fixata the angle of the cut; 2) opposite ventrofixatio uteri retroflexi ad hoc, which should be considered as a life-threatening operation undertaken to cure non-life-threatening suffering, can only be tolerated with retroflexio fixata.

In cool climates, crayfish that are not primary burrowing species are typically thought to retreat into deeper waters in winter and may seek refuge in small aquatic burrows or interstitial spaces associated with aquatic substrates. Herein, I report a novel observation of a juvenile Cambarus bartonii bartonii (Common Crayfish) during winter within eastern Pennsylvania occupying a terrestrial microhabitat consisting of moist, terrestrial leaf litter associated with a small depression in an upland forest. I found the crayfish in association with a small aggregation of Plethodon cinereus (Eastern Red-backed Salamander). Requirements of a hibernaculum by the salamanders with sufficient moisture and buffered from freezing may have also provided sufficient conditions for the crayfish to utilize the depression as a winter refugium.

The Atacama Desert is one of the driest and probably oldest deserts on Earth where only a few extremophile organisms are able to survive. This study investigated two terricolous and two epiphytic lichens from the fog oasis “Las Lomitas” within the National Park Pan de Azúcar which represents a refugium for a few vascular desert plants and many lichens that can thrive on fog and dew alone. Ecophysiological measurements and climate records were combined with molecular data of the mycobiont, their green algal photobionts and lichenicolous fungi to gain information about the ecology of lichens within the fog oasis. Phylogenetic and morphological investigations led to the identification and description of the new lichen species Acarospora conafii sp. nov. as well as the lichenicolous fungi that accompanied them and revealed the trebouxioid character of all lichen photobionts. Their photosynthetic responses were compared during natural scenarios such as reactivation by high air humidity and in situ fog events to elucidate the activation strategies of this lichen community. Epiphytic lichens showed photosynthetic activity that was rapidly induced by fog and high relative air humidity whereas terricolous lichens were only activated by fog., The Atacama Desert is one of the driest and probably oldest deserts on Earth where indigenous lichens are reported to grow. This article presents the phylogeny of two epiphytic and two terricolous lichens, their photobionts and fungal parasites and describes their eco‐physiological adaptations.

A flume was used to estimate the carrying capacity of streambed substrates for juvenile steelhead or rainbow trout Oncorhynchus mykiss seeking refuge from simulated freshets. The simulated freshets had mean water column velocities of c. 1·1 m s(-1). The number of O. mykiss finding cover within the interstices of the substrate was documented for different substrate sizes and levels of embeddedness. The availability of suitable refuges determined the carrying capacity of the substrate for O. mykiss. For the size of the O. mykiss tested [mean ± s.d. fork length (L(F)) = 122 ± 12.6 mm], the number of interstices with depths ≥200 mm measured with a 14.0 mm diameter flexible plastic tube was the best predictor of the number of O. mykiss able to find cover (r(2) = 0.75). Oncorhynchus mykiss seeking refuge from freshets may need deeper interstices than those seeking concealment at autumn or winter base flows. The availability of interstices suitable as refuge from high flows may determine autumn and winter carrying capacity.

Terrapene carolina (Eastern Box Turtle) is the only turtle species in which adults are known to be tolerant of freezing. We report the first systematically collected data on internal body temperatures of an overwintering Eastern Box Turtle. Despite nearby air temperatures as low as -21.8 °C, this turtle probably supercooled rather than froze. Snow cover, thermal inertia, and the insulating effects of its refugium's substrate may have protected this turtle from the very cold conditions.

Tekst poświęcony jest analizie różnych form miłości w warszawskim getcie: caritas (agape), filia (dilectio) i eros (amor) oraz asylum (refugium) – właściwej doświadczeniom krańcowym. Na przykładzie zapisków osobistych i relacji powojennych autorka opisuje rozmaite przykłady tych czterech rodzajów miłości.

We examined the distribution and co-occurrence of the exotic digenetic trematode Centrocestus formosanus, its exotic intermediate host the red-rim melania snail Melanoides tuberculatus, and rates of infection of fish in 10 spring systems throughout western Texas during 1999 and 2011. Four of the spring systems (East Sandia Springs, Independence Creek, Big Bend National Park Refugium Pond, and Clear Creek) did not contain red-rim melania snails in 1999 and 2011. Four spring systems that were populated with snails (San Felipe Creek, San Solomon Springs, Phantom Lake, and Diamond Y Springs) contained the trematode and were positive for branchial infection in fish except Diamond Y Springs which contained uninfected snails and fish. Since 1999, two additional spring systems, Pinto Creek and Devils River, contained the trematode. We found a high prevalence of branchial infection for fish collected regardless of species. Seventeen of the 21 species of fish collected from the spring systems were positive...

Occurrence and breeding of Hirudo medicinalis were recorded in birds’ nests in the fishing ponds and water bodies used extensively by anglers in south-eastern Poland, in 4 of 11 studied bird species (Circus aeruginosus, Fulica atra, Cygnus olor, Chroicocephalus ridibundus). Factors important for the distribution and density of this leech were: nest height, pH of the water and oxygen concentration in the water inside the nests, the body-length of the nesting birds. Our data show that (1) H. medicinalis chooses nests as habitats that are safe in water bodies rich in predators (particularly fish) and provide stable feeding conditions; (2) fishing ponds and other water bodies used extensively by anglers in a landscape modified by human pressure can be an important secondary habitat for the medicinal leech. As the nesting activity of some aquatic birds apparently favors the occurrence of H. medicinalis, active protection of aquatic birds and creating sites appropriate for their breeding may be an indirect way for the conservation of the leech in such areas.

This article describes the initial season‐long yield trial of raising the endangered Rio Grande silvery minnow, Hybognathus amarus, in the conservation rearing facility at the Los Lunas Silvery Minnow Refugium. Ten thousand fish (90,900/ha) were stocked on June 22, 2010. Production was based on a total of 653 mL (5.936 L/ha) of 11‐37‐0 N‐P‐K and 5.5 kg (50 kg/ha) of alfalfa pellets. Fish were harvested in October; almost all were harvested 18–27 October. At stocking, fish averaged 21.7 mm total length and mean weight was 0.10 g. At harvest, fish averaged 48.98 mm and 1.12 g. Fish were sampled monthly, and increased lengths and weights through the study were significant (P = 0.05). Five thousand eight hundred ninety‐two fish were harvested (58.92% survival). Yield was 59.99 kg/ha. Temperature, dissolved oxygen (DO), pH, un‐ionized ammonia, nitrite, turbidity, alkalinity, and chloride were measured at seven sites throughout the outdoor refugium. Secchi disc visibility was measured in the stream and in the ponds. Only two variables (DO and pH) went outside permitted values, but were easily corrected. Harvest was difficult due to the many different naturalized areas consisting of varying depths, channel widths, and substrates.

We observed aggregations of westslope cutthroat trout Oncorhynchus clarkii lewisi, mountain whitefish Prosopium williamsoni, and to a lesser extent, rainbow trout Oncorhynchus mykiss moving into cold side channels in the North Fork Coeur d’Alene River in northern Idaho during the summer of 2007. The use of cold side channels varied throughout the season, as well as by size-class. Such use was much greater for salmonids 300 mm or more in length, and the movement of salmonids into side channel habitats appeared to be triggered by rising water temperatures in the main river and temperature divergences between the main river and the side channels. Larger salmonids were not evenly distributed among the side channels, and channel physical features varied widely. The probability that a side channel would be used as a thermal refugium by salmonids 300 mm or more appeared to be influenced by channel depth, and salmonids of that size used side channels that were both deep (≥2 m) and cold (≤20°C). Protectio...

Summary Critical swimming speeds of sturgeon are presumably lower in vertically uniform, rectilinear flow than in heterogeneous boundary-layer flow. Movement in rectilinear flow of the water column necessitates frequent high-energy free-swimming, while movement in boundary-layers near the bottom of the river permits a variety of lower energy behaviours, and presumably, negotiation of greater mid-column water velocities. Comparative studies of sturgeon swimming performance in rectilinear and boundary layer flows, however, are lacking. Using a 1200-l laboratory swim tunnel, swimming performance was measured for 12 adult shovelnose sturgeon (Scaphirhynchus platorynchus), 494–705 mm standard length. Tests were conducted at 20–25� C in rectilinear (N = 4) and boundary-layer flows (N = 8). Fifteen minute critical swimming speeds ranged from 89.3 to 112.6 cm s )1 in rectilinear flow, 129.5–172.1 cm s )1 in boundary-layer flow. Higher critical swimming speeds observed in boundary-layer flows was a combination of behavioural adaptations (body appression to flat, horizontal substrate) and availability of a low velocity refugium (water velocities at bottom of tank 21– 65 cm s )1 slower than those in mid and upper levels of tank). Results support the idea that sturgeon exploit boundary-layers to effectively move or hold position in fast-flowing rivers. Data may be applied to man-made river structures to facilitate fish passage and to reduce risk of sturgeon entrainment.

SUMMARYFactors constraining host specificity are poorly understood. Intraspecific variation in host preferences in generalist parasites may reveal which factors affect patterns of host use, and thus the evolution of specialization. Here, laboratory experiments examined genetic variation in host preferences and the effect of a refugium against infection on host use. Firstly, 6 cercarial clones of the trematodeMaritrema novaezealandensis(ranging widely in heterozygosities) were exposed simultaneously to 2 alternative hosts, the amphipodsHeterophoxus stephenseniandParacalliope novizealandiae,to assess host preferences and fitness correlations with parasite heterozygosity. All clones showed a distinct preference forH. stephenseni, though the extent of this preference varied among clones. No clear association was found between heterozygosity and either parasite infection success or preference for a particular host. Secondly, cercariae were exposed to the same 2 amphipods in both the presence and absence of sand (refugium forH. stephenseni). Without sand, infection levels were significantly higher inH. stephensenithan inP. novizealandiae. With sand,H. stephenseniwas able to hide, offsetting the parasite's intrinsic preferences for this host. These results demonstrate the existence of genetic variation in host preferences, as well as the effect of environmental variables on observed patterns of host use.

Most juveniles of Haliotis discus hannai have been found to be descendants of wild individuals, although most adults were artificially produced (released) individuals as a result of restocking inside the refugium located near the head of Oshoro Bay, Hokkaido, Japan. To estimate the larval supply from released and wild individuals into the refugium and to compare the suitability of locations as larval sources, we simulated larval dispersal using a coupled hydrodynamic and particle-tracking model. The simulation results indicated that more larvae may be supplied from the wild adults inside the bay to the refugium than from the released adults. These results are consistent with the observed high abundance of wild juveniles in the refugium. Most larvae from the refugium were predicted to disperse out of the bay. We found that larval retention in the bay was at least one order of magnitude higher than that in the refugium. Thus, it may be more effective in terms of self-replenishment and reproduction if the refugium were to be expanded to the bay scale. There were only minor differences among the compared sites at the head of the bay in terms of their suitability as larval sources. Consequently, the establishment of new refugia in this area could be expected to provide an effectiveness equal to that of the current refugium.

Traian Orghidan's seminal paper on the hyporheic zone was published in German in Archiv fur Hydrobiologie 50 years ago. To celebrate this anniversary, it has now been translated into English and republished in Fundamental and Applied Limnology, the successor to Archiv fur Hydrobiologie, as part of this special issue on hyporheic zone ecology. Here we examine the development and current state of knowledge of four aspects of hyporheic zone ecology first articulated by Orghidan. First, we consider the ecotonal nature of the hyporheic zone (HZ) and its relationship to the wider stream ecosystem; second, surface water and groundwater habitat interconnectivity within the hyporheic zone; third, the spatial and temporal heterogeneity of the HZ and how this may influence its function as a refugium for taxa during disturbances; and lastly interactions between hyporheic invertebrates and pore water volume, bacterial densities and particulate organic carbon. We outline the characteristics of the hyporheic zone that may determine how effective it will be as a refugium for benthic taxa during disturbances and consider the biological traits of benthic species most able to utilise the HZ as a refugium. Finally, we examine an important avenue of research that has developed since Orghidans paper reflecting significant scientific and technological advances; the role of the hyporheic zone in stream nutrient dynamics. We conclude by considering some areas where further research is likely to advance our understanding of the hyporheic zone and its interaction with the wider stream ecosystem.

Goląb M.J., Lipinska A.M., Cmiel A.M.: The consequences of water release from a dam reservoir for freshwater mussel survival: recommendations for improved management. ekologia (Bratislava), vol. 29, no. 4, p. 454–459, 2010. dam reservoirs may play an important role in threatened freshwater mussel conservation. However, the restoration works on a dam and their consequences can threaten whole mussel populations. This study investigates the consequences of water release in the Czorsztyn reservoir in order to improve management of dam reservoirs. The analysis shows that the reservoir’s water releases caused massive death of freshwater mussels. The main threat for mussel survival was probably flat slopes that disturbed both their ability to perceive slope gradient and the possibility to escape. in order to decrease the losses of freshwater mussel populations, it is necessary to remodel a part of the reservoir bowl’s shore and to create a refugium for the mussels. if terracing across the slopes is necessary, the steps should not be entirely plain, but tilted towards the water.

A coupled particle-tracking and hydrodynamic model, into which observed current data were assimilated, was used to simulate larval dispersal of large abalone (Haliotis discus discus, H. gigan- tea, and H. madaka) in Sagami Bay, Japan. The aims of this study were to (1) clarify larval dispersal pro- cesses and settlement sites, and (2) evaluate the existing harvest refugium and estimate the suitability of other areas for larval sources, using this model. In the larval dispersal simulations, particles were re- leased at the time of hatching, which was calculated from the estimated time of fertilization/potential spawning and based upon the water temperature. The results of larval dispersal simulations indicate 2 different dispersal patterns: (1) transport toward the coast after dispersal offshore, and (2) gradual dis- persal offshore. The refugium was compared with 3 hypothetical reproductive sources located 1 km north, west, and south of the refugium. During settlement competency, transport success (transport to the area at the depth of adult habitat: ≤ 30 m) of particles released at the refugium was highest (27 to 75%), and suggested that the location of this refugium was more suitable for a larval source than those of the hypothetical reproductive sources. Multiple potential larval settlement sites were identified. These results have important implications for refugium design at the study site. The method and model devel- oped in the present study could be used for evaluating harvest refugia and for identifying effective lo- cations for reproductive sources and potential settlement sites.

The construction of salmon redds represents a localized but intense disturbance to benthic substrate and associated flora and fauna. Pink salmon (Oncorhynchus gorbuscha) have a fixed 2-y life cycle. Thus, their spawning run in Wolf Point Creek, a 1st-order coastal stream in southeast Alaska, alternates between high-density (odd years) and low-density (even years) returns. During July and August 1996 and 1998, counts of returning fish were low ( 10,000 fish, and streambed disturbance was extensive. Coarse particulate organic matter and macroinvertebrate density and taxonomic richness were significantly lower in the main channel in 1997 than in 1996 or 1998. Macroinvertebrate densities and taxonomic richness were similar in all years in areas unsuitable for salmon redds (refugium habitat: margins, boulders, shallows). Macroinvertebrate drift density increased during the 1997...

Eggs-per-recruit (EPR) models are widely used for management of invertebrate fisheries to provide guidance to managers about the magnitude of egg production for a given level of instantaneous annual fishing mortality (F). We constructed a deterministic size-based EPR model that utilizes size-specific natural mortality rates and egg production for red abalone Haliotis rufescens in California. We analyzed the sensitivity of the model to alterations in biological parameters, modeled the effect of incidental mortality of sublegal individuals on EPR, and modeled the effects of various management actions, including incorporation of a slot size limit, incorporation of a harvest refugium, and alternative legal minimum size limits. Model results were more sensitive to alterations in growth parameters and lower mortality estimates than to changes in upper mortality estimates or fecundity parameters. When F increased from 0.0 to 0.1 per year, EPR exhibited a large decline from 100% to 70%. Only the incorporation of a harvest refugium and an increase in the minimum size limit produced increases in the percent of maximum EPR. Implementing a slot limit of 152.4-203.2 mm maximum shell length (MSL) decreased the EPR value, indicating the importance of egg production by red abalone that are smaller than the current minimum size limit of 177.8 mm MSL. Because of the sensitivity of model predictions to changes in certain biological parameters, we recommend caution when applying EPR models to management, particularly for regions without spatially explicit parameter values. Despite this sensitivity, EPR models provide a heuristic framework for exploring the potential impacts of proposed fishery management strategies (e.g., harvest refugia), establishing biological reference points, examining how spatial and temporal variability in biological parameters affects egg production, and providing a guide for prioritizing research to improve data quality used for red abalone management.

Like all terrestrial arthropods, mosquitoes must cope with the threat of desiccation. To gain insight into their survival strategies, we recorded the behavioral responses of Anopheles gambiae, Anopheles stephensi, Aedes aegypti, and Culex pipiens offered zones of different microclimatic conditions in laboratory cages. The cooled refugium was at 25.6 degrees C, 86% RH and the control was at 28.5 degrees C, 75% RH, i.e., a difference in saturation deficit of 3.9 mm Hg between the two zones. We show that newly-emerged adults, with no access to water or sugar, prefer the cooler and more humid refugium with a saturation deficit half that in the control and where the mosquitoes could reduce their metabolic rate. This response is delayed in Ae. aegypti, perhaps because the energy reserves accumulated as larvae are higher in this species. This study shows that mosquitoes under stress can use their thermohygroreceptor cells to guide them to locations that facilitate survival.

[Breeding strategies of hydrothermal vent biota are of central interest for the "supply-side" ecology and evolution at vent sites. Researchers from the National Taiwan Ocean University have recently uncovered a new nursery habitat for the vent crab, Xenograpsus testudinatus (Decapoda, Brachyura) at a shallow hydrothermal vent site that extends from the deep-sea Okinawa Trench, off the northeastern coast of Taiwan (N.W. Pacific Ocean). Megalopa and early juvenile crab stages were found abundantly in a fissured habitat: sulfur aggregates around the chimneys of the vent system. The present underwater visual observations at hydrothermal vent systems at depths of around 20 metres indicate that sulfur rock aggregates are a primary nursery habitat for early benthic crab stages. They provide shelter from physical and biotic disturbance. This finding may explain why hydrothermal vents from the shallows to the deep sea provide suitable habitats for crabs to become astoundingly flourishing and dominant in all hydrothermal vent systems. Fortpflanzungsstrategien der Biota von Hydrothermalquellen sind von zentralem Interesse fur das Verstandnis von Verbreitung und Evolution der Lebensformen an Hydrothermalquellen. Wissenschaftler von der "National Taiwan Ocean University" haben ein neues Refugium fur larvale und juvenile Stadien des Kurzschwanzkrebses Xenograpsus testudinatus (Decapoda, Brachyura) an einer Hydrothermalquelle des Flachwassers entdeckt. Diese befindet sich an der Nordostkuste Taiwans (N.W. Pazifischer Ozean) in Verlangerung des Okinawa Grabens. Megalopa Larven und juvenile Stadien dieses Krebses wurden in dichten Ansammlungen in einem reich texturierten Habitat entdeckt: in Schwefelaggregaten, die um die Schornsteine von Hydrothermalquellen herum angeordnet sind. Die hier gemachten Unterwasserbeobachtungen im Bereich von Hydrothermalquellen, in Tiefen von etwa 20 Metern, zeigen Schwefelaggregate als Refugien der fruhen benthischen Stadien dieser Kurzschwanzkrebse. Dieses Habitat bietet Schutz vor physischen und biotischen Storungen. Diese Entdeckung mag zusatzlich erklaren, warum Kurzschwanzkrebse an Hydrothermalquellen erstaunlich hohe Dichten aufweisen konnen., Breeding strategies of hydrothermal vent biota are of central interest for the "supply-side" ecology and evolution at vent sites. Researchers from the National Taiwan Ocean University have recently uncovered a new nursery habitat for the vent crab, Xenograpsus testudinatus (Decapoda, Brachyura) at a shallow hydrothermal vent site that extends from the deep-sea Okinawa Trench, off the northeastern coast of Taiwan (N.W. Pacific Ocean). Megalopa and early juvenile crab stages were found abundantly in a fissured habitat: sulfur aggregates around the chimneys of the vent system. The present underwater visual observations at hydrothermal vent systems at depths of around 20 metres indicate that sulfur rock aggregates are a primary nursery habitat for early benthic crab stages. They provide shelter from physical and biotic disturbance. This finding may explain why hydrothermal vents from the shallows to the deep sea provide suitable habitats for crabs to become astoundingly flourishing and dominant in all hydrothermal vent systems. Fortpflanzungsstrategien der Biota von Hydrothermalquellen sind von zentralem Interesse fur das Verstandnis von Verbreitung und Evolution der Lebensformen an Hydrothermalquellen. Wissenschaftler von der "National Taiwan Ocean University" haben ein neues Refugium fur larvale und juvenile Stadien des Kurzschwanzkrebses Xenograpsus testudinatus (Decapoda, Brachyura) an einer Hydrothermalquelle des Flachwassers entdeckt. Diese befindet sich an der Nordostkuste Taiwans (N.W. Pazifischer Ozean) in Verlangerung des Okinawa Grabens. Megalopa Larven und juvenile Stadien dieses Krebses wurden in dichten Ansammlungen in einem reich texturierten Habitat entdeckt: in Schwefelaggregaten, die um die Schornsteine von Hydrothermalquellen herum angeordnet sind. Die hier gemachten Unterwasserbeobachtungen im Bereich von Hydrothermalquellen, in Tiefen von etwa 20 Metern, zeigen Schwefelaggregate als Refugien der fruhen benthischen Stadien dieser Kurzschwanzkrebse. Dieses Habitat bietet Schutz vor physischen und biotischen Storungen. Diese Entdeckung mag zusatzlich erklaren, warum Kurzschwanzkrebse an Hydrothermalquellen erstaunlich hohe Dichten aufweisen konnen.]

In grazing cattle, infections with gastrointestinal nematodes pose some of the most important health threats and subclinical infections result in considerable production losses. While there is little doubt that climate change will affect grazing ruminants directly, mean temperature increases of ∼ 3°C and longer drought stress periods in summer may also influence the free-living stages of parasitic nematodes. Hostile climatic conditions reduce the number of L3s on pasture and therefore the refugium, which is expected to result in a higher selection pressure, accelerating development of resistance against anthelmintic drugs. The aim of the current experiments was to investigate the effects of drought stress and different temperature/humidity ranges over time on the survival and fitness of Cooperia oncophora L3s and their distribution in grass and soil under controlled conditions using a climate chamber. Grass containers inoculated with L3s were analysed after 1-6weeks using descriptive statistics as well as linear models. A large proportion of L3s was recovered from soil where fitness was also better preserved than on grass. Numbers and fitness of recovered L3s declined with duration in the climate chamber under both temperature profiles. However, the results of the linear models confirmed that higher temperatures (20-33°C versus 17-22.6°C) significantly impaired survival, distribution and fitness of L3s. Application of drought stress, known as another important factor, had a surprisingly smaller impact than its duration or higher temperatures. The climate chamber enabled exclusion of confounding factors and therefore accurate interpretation of the investigated climatic aspects. The obtained results highlight the relative importance of those factors, and will help to design better models for the population dynamics of L3s on pasture in the future. Additionally, the outcomes of these investigations may offer explanations regarding interdependencies of development of anthelmintic resistance and the presence of hot/dry weather conditions.

Summary Due to their special geographic circumstances, some places on earth are resistant to global warming. But a new study of an arctic refugium suggests it's only a matter of time before climate change breaches the defenses. Cyrus Martin reports.

Enumeration of benthic (bottom dwelling) and epiphytic (attached to plants) zebra and quagga mussels (Dreissena polymorpha and D. bugensis, respectively) at Lake Erie near-shore sites in fall of 2000 revealed an unexpected prevalence of the zebra mussel on submerged plants. Even at Buffalo, New York, USA, where benthic dreissenids have been 92–100% quagga mussel since 1996, zebra mussels constituted 30–61% of epiphytes numerically. This may reflect a partitioning of settling space consistent with interspecific competition. A seasonal epiphytic refugium might allow the zebra mussel to persist even where the benthos is almost exclusively quagga mussel.