Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.

This study investigated the structure and innervation of the vibrissal systems of the pole cat (Mustela putorius), European otter (Lutra lutra) and ringed seal (Phoca hispida) in order to find adaptations to aquatic environment. The number of myelinated nerve fibers of deep vibrissal nerve (DVN) of the entire vibrissal system was considerably greater in the ringed seal (10×, aquatic mammal) and in the otter (4×, semi-aquatic mustelid) compared to the pole cat which is a terrestrial mustelid. Similarly, the number of neural end organs in the vibrissae of ringed seals was about ten times more numerous than in pole cats. The number of the vibrissae in the heads of otters was almost two times more than in pole cats, and all vibrissa groups had similar structures and innervation. The asymmetrically developed carpal vibrissae of otters were, however, more poorly innervated than the vibrissae of the head and had only smooth musculature. In the ringed seal the orientation of lanceolate end organs differed in different vibrissae, indicating the specialization of these vibrissae for different kinds of sensory functions. Ringed seal vibrissae contain structures which obviously are developed as adaptations to an aquatic environment. These include the modified mitochondria of Merkel cells, with Merkel cell-neurite complexes very often associated ciliated cells, liquid filled vesicles or intercellular spaces below the basal cell layer of the outer root sheath at the ring sinus level, a long upper cavernous sinus and a flattened beaded structure of the vibrissa hairs. As the vibrissae of aquatic mammals have analogous functions to the lateral line organ of fishes, we suggest using the term ‘vibrissal sense’ for the vibrissa system of aquatic mammals.

Marine Mammal ScienceVolume 25, Issue 4 p. 920-930 Vocal repertoire of the Saimaa ringed seal (Phoca hispida saimensis) during the breeding season Anni Rautio, Anni Rautio Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandE-mail: [email protected]Search for more papers by this authorMarja Niemi, Marja Niemi Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandE-mail: [email protected]Search for more papers by this authorMervi Kunnasranta, Mervi Kunnasranta Finnish Game and Fisheries Research Institute, Turku Game and Fisheries Research, Itäinen Pitkäkatu 3A, FI-20520 Turku, FinlandSearch for more papers by this authorIsmo J. Holopainen, Ismo J. Holopainen Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandSearch for more papers by this authorHeikki Hyvärinen, Heikki Hyvärinen Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandSearch for more papers by this author Anni Rautio, Anni Rautio Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandE-mail: [email protected]Search for more papers by this authorMarja Niemi, Marja Niemi Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandE-mail: [email protected]Search for more papers by this authorMervi Kunnasranta, Mervi Kunnasranta Finnish Game and Fisheries Research Institute, Turku Game and Fisheries Research, Itäinen Pitkäkatu 3A, FI-20520 Turku, FinlandSearch for more papers by this authorIsmo J. Holopainen, Ismo J. Holopainen Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandSearch for more papers by this authorHeikki Hyvärinen, Heikki Hyvärinen Faculty of Biosciences, University of Joensuu, P. O. Box 111, FI-80101 Joensuu, FinlandSearch for more papers by this author First published: 22 October 2009 https://doi.org/10.1111/j.1748-7692.2009.00299.xCitations: 13Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Literature Cited Asselin, S., M. O. Hammill and C. X. Barette. 1993. Underwater vocalization of ice breeding grey seals. Canadian Journal of Zoology 71: 2211–2219. Calvert, W., and I. Stirling. 1985. 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Sipilä and N. Medvedev. 2001. Breeding habitat and lair structure of the ringed seal (Phoca hispida ladogensis) in northern Lake Ladoga in Russia. Polar Biology 24: 171–174. Kunnasranta, M., H. Hyvärinen and J. Sorjonen. 1996. Underwater vocalizations of Ladoga ringed seals (Phoca hispida ladogensis Nordq.) in summertime. Marine Mammal Science 12: 611–618. Mann, D. A., T. J. O'shea and D. P. Nowacek. 2006. Nonlinear dynamics in manatee vocalizations. Marine Mammal Science 22: 548–555. McCulloch, S., P. P. Pomeroy and P. J. B. Slater. 1999. Individual distinctive pup vocalizations fail to prevent allo-suckling in grey seals. Canadian Journal of Zoology 77: 716–723. Miller, E. H., and A. V. Murray. 1995. Structure, complexity, and organization of vocalizations in harp seal (Phoca groenlandica) pups. Pages 237–264 in R. A. Kastelein, J. A. Thomas and P. E. Nachtigall, eds. Sensory systems of aquatic mammals. De Spil Publishers, Woerden , The Netherlands . Møhl, B., J. K. Terhune and K. Ronald. 1975. Underwater calls of the harp seal (Pagophilus groenlandicus). Pages 533–543 in K. Ronald, K. and A. Mansfield, eds. Biology of the seal. Imprimerie Bianco Luno A/S, Copenhagen , Denmark . Nordquist, O. 1899. Beitrag zur kenntniss der isolierten formen der ringelrobbe (Phoca foetida Fabr.). Acta Societatis Pro Fauna et Flora Fennica 15: 1–43. Ray, G. C., and W. A. Watkins. 1975. Social function on underwater sounds in the walrus Odobenus rosmarus. Pages 524–526 in K. Ronald, K. and A. Mansfield, eds. Biology of the seal. Imprimerie Bianco Luno A/S, Copenhagen , Denmark . Renouf, D. 1984. The vocalization of the harbor seal pup (Phoca vitulina) and its role in the maintenance of contact with the mother. Journal of Zoology, London 202: 583–590. Schevill, W. E., W. A. Watkins and C. Ray. 1963. Underwater sounds of pinnipeds. Science 141: 50–53. Sipilä, T. 1990. Lair structure and breeding habitat of the Saimaa ringed seal (Phoca hispida saimensis Nordq.) in Finland. Finnish Game Research 47: 11–20. Sipilä, T. 2003. Conservation biology of Saimaa ringed seal (Phoca hispida saimensis) with reference to other European seal populations. Ph.D. dissertation, University of Helsinki, Helsinki , Finland . 40 pp. Sipilä, T., and H. Hyvärinen. 1998. Status and biology of Saimaa (Phoca hispida saimensis) and Ladoga (Phoca hispida ladogensis) ringed seals. Pages 83–99 in M. P. Heide-Jørgensen and C. Lydersen, eds. Ringed seals in the North Atlantic: No 1. The North Atlantic Marine Mammal Commission (NAMMCO) Scientific Publications, Tromsø , Norway . Sipilä, T., N. V. Medvedev and H. Hyvärinen. 1996. The Ladoga seal (Phoca hispida ladogensis Nordq.). Hydrobiologia 322: 193–198. Sjare, B. L., and I. Stirling. 1991. I hear you knocking. Natural History 100(3): 60–63. Sjare, B., I. Stirling and C. Spencer. 2003. Structural variation in the songs of Atlantic walruses breeding in the Canadian High Arctic. Aquatic Mammals 29: 297–318. Stirling, I. 1973. Vocalization in the ringed seal (Phoca hispida). Journal Fisheries Research Board of Canada 30: 1592–1594. Stirling, I., W. Calvert and H. Cleator. 1983. Underwater vocalizations as a tool for studying the distribution and relative abundance of wintering pinnipeds in the High Arctic. Arctic 36: 262–274. Stirling, I., W. Calvert and C. Spencer. 1987. Evidence of stereotyped underwater vocalizations of male Atlantic walruses (Odobenus rosmarus rosmarus). Canadian Journal of Zoology 65: 2311–2321. Thomas, J. A., and V. B. Kuechle. 1982. Quantitative analysis of Weddell seal (Leptonychotes weddellii) underwater vocalization at McMurdo Sound, Antarctica. Journal of Acoustical Society of America 72: 1730–1738. Van Opzeeland, I. C., and S. M. Van Parijs. 2004. Individuality in harp seal, Phoca groenlandica, pup vocalizations. Animal Behaviour 68: 1115–1123. Van Parijs, S. M., and K. M. Kovacs. 2002. In-air and underwater vocalizations of eastern Canadian harbour seals, Phoca vitulina. Canadian Journal of Zoology 80: 1173–1179. Wilden, I., H. Herzel, G. Peters and G. Tembrock. 1998. Subharmonics, biphonation, and deterministic chaos in mammal vocalization. Bioacoustics 9: 171–196. Citing Literature Volume25, Issue4October 2009Pages 920-930 ReferencesRelatedInformation

The physiological responses of juvenile rainbow trout (Oncorhynchus mykiss) to lithium (as LiCl) in moderately hard freshwater (CaCO3 = 120–140 ppm, Na+ = ∼0.6 mM) were studied. The study employed a 15-day step-up exposure regime; 66 μg/L Li for the first 9 days and 528 μg/L for the next 6 days. The concentrations of plasma ions, apolipoprotein AI, total cholesterol, and fatty acids, as well as metabolic enzyme citrate synthase (CS) and Na+,K+-ATPase activities in the gill were measured. Li affected fish by exacerbated diffusive Na+ losses at the gills in the beginning of exposure and a decrease of branchial CS activity. Detrimental effects were shown in fish exposed to 528 μg Li/L. These included a reduction of gill Na+,K+-ATPase activity, possibly related to observed lower concentrations of free fatty acids and cholesterol in gill tissue.

The objective of this study is to discern the effects of increased waterborne lithium and potassium on rainbow trout gill histology, lipid composition, and enzyme activity. The study aims to elucidate the effects of these ions in the laboratory in concentrations similar to those prevailing in a forest lake Poppalijärvi in a contaminated mining area in NW Russia. Under the lithium and potassium exposure, the fish were further stressed by high pH (8.2 as in Lake Poppalijärvi) and lack of food. These multiple stress conditions altered the gill membrane fluidity by increasing sphingomyelin (5.5+/-0.6 compared to 2.9+/-0.3% in the control) and reducing cholesterol (4+/-1 compared to 17+/-3 mg g(-1) in the control). The total ATPase activity tended to be higher in the lithium-potassium-exposed group (46+/-6 compared to 34+/-2 micromol Pi h(-1) mg(-1)protein in the control). Lithium toxicity was lowered here by the protective role of higher potassium contents.

(2006). Benthic macroinvertebrates in lakes affected by iron mining waste waters in the Kostomuksha area, northwest Russia. SIL Proceedings, 1922-2010: Vol. 29, No. 4, pp. 2039-2044.

Biomass and species diversity (richness and evenness) of littoral organisms were explored in 27 sites in three basins of the large Lake Saimaa system in eastern Finland. The basins differed in degree of nutrient loading and trophic status. Six organismal groups, i.e., phytoplankton, periphyton, macrophytes, crustacean zooplankton, benthic macroinvertebrates and fish were studied. Factors affecting the biomass and diversity of these groups were explored by multiple stepwise regression analysis. The biomass of different groups was explained by the same variables, mainly nutrients, while diversity was associated with different environmental factors among the studied groups. The biomass of periphyton, phytoplankton, zooplankton, and fish correlated significantly with each other. There was also an apparent association between the biomass of macrophytes and that of benthic invertebrates. However, no significant correlations were found among the diversity of the studied groups. In accordance with previous studies, our results did not support the existence of species-rich hotspots or the possibility of using any surrogate taxon to reveal overall biodiversity. Thus, for conservation planning, biological surveys should include extensive collection of taxonomic groups and organisms at all trophic levels.

Accumulation and toxicity of waterborne bisphenol A were studied in landlocked salmon (Salmo salar m. sebago) yolk-sac fry. In a short-term (96 h) exposure to five bisphenol A concentrations yolk-sac fry had higher accumulation rates and bioconcentration factors (BCF96) than earlier studies have shown for salmon eggs. Furthermore, the conditional uptake rate constant tended to decrease as exposure concentration increased. Fry were also exposed to bisphenol A for 42 days at three concentrations (10, 100 and 1000 μg/l), and changes in behaviour, morphology and histological structure were observed. After 6 days of exposure, the highest concentration (1000 μg/l) of bisphenol A caused fluid accumulation (oedema) in the yolk sac and haemorrhages in the front part of the yolk sac and in the head around the gill arches. Later on, the fry at 1000 μg/l showed phlegmatic behaviour and had darker skin coloration than the fry in the other treatments. At the two highest concentrations (100 and 1000 μg/l) histological changes were seen in liver cell nuclei, where strongly stained fragments were observed. In the control fry and the fry exposed to 10 μg/l the nucleolus was clearly visible and spherical in shape and no strongly stained fragments were present. This study shows that high concentrations of bisphenol A may have both morphological and histological effects on salmon yolk-sac fry.

Variation in substrate association types and maximum size of aquatic insects were studied in a vegetated littoral zone of three lake basins. The basins differed from each other in trophic status, biomass of benthivorous fish, and abundance of macrophytes. Four types of substrate association – swimmers, crawlers, semisessiles and burrowers, respectively – were assumed to represent decreasing vulnerability to fish predators. Large-sized species were also hypothesised to be more vulnerable to fish predators. The distributions of species traits were examined in relation to vegetation density. Inferring from ``predation hypothesis'' opposite selection pressures on the species traits were expected along the vegetation density. Dense macrophyte beds were thought to be dominated by invertebrate predators and open water by fish predators, since the predation efficiency of fish decreases in complex environments. In the case of invertebrate predator domination, large size and higher activity should be favoured traits among the prey species. Distribution patterns of modes of the two studied traits were explored separately for predatory and non-predatory insects. As expected, swimmers and large-sized crawlers were characteristic of the insect assemblages of dense macrophyte beds. The densities of Odonata, Corixidae, Dytiscidae, Ephemeroptera and Sialidae were higher among macrophytes than in open water, where these insect taxa were possibly depleted by fish. On the other hand, the small-sized and fairly immobile Chironomidae were the most abundant group in open water. These results support the existence of a predator transition zone among littoral vegetation, ranging from domination of invertebrate predation among the dense beds to that of fish predation in open water.

Sublethal effects of pentachlorophenol (PCP) were studied in the freshwater clam Pisidium amnicum by examining the cause-effect relationship between PCP body burden and the rate of the whole animal heat output. In addition, the modifying effects of temperature (7 and 15 degrees C) and trematode parasites as natural stress factors were assessed. Results showed that even a low PCP body burden was sufficient to increase the heat output during the periods of aerobic metabolism and the magnitude of responses increased linearly with increasing body burden. During a valve-closure period, however, PCP had no effect on anaerobic heat output. The rise of the maximum heat output in response to PCP was more pronounced at the higher temperature. The response in heat output was similar in both infected and uninfected clams, but the general level of heat output was lower in infected clams. The increasing PCP body burden also increased the duration of valve-closure time. The results of this study suggested that microcalorimetry could be a useful tool in assessing sublethal responses by the clam, which offers several calorimetrically measurable parameters such as aerobic and anaerobic heat output and behavior.

The mining company Karelian Pellet in northwestern Russia extracts iron ore and processes it locally into pellets. The production operations affect the environment in the form of air pollution and wastewater emissions to lakes downstream from the factory. The toxic effects of the mining effluents on gills of perch (Perca fluviatilis) and roach (Rutilus rutilus) were studied. In lakes close to the factory, heavy metal concentrations in gills were not high, even though the metal content in sediment was elevated. In fish gills the relative proportion of phosphatidylcholine was elevated and cholesterol reduced, while the histological structure of the gills was changed. The number of mucus cells, as well as the sizes and the lengths of open areas in the chloride cells, had increased in spring and summer. The hypertrophy of chloride cells is possibly caused by the increased ambient concentrations of K+ and Li+. Changes in gill cholesterol and phospholipid proportions increase the fluidity of membranes and possibly strengthen their protective qualities, counterbalancing the adverse changes in chloride cell structure. The bioavailability and toxic effects of metals on fish are reduced by the hardness and high pH of water discharged by the mining plant.

The mining company Karelian Pellet in NW Russia extracts iron ore and processes it locally into iron pellets. The production operations have effects on the environment in the form of air pollution (SO2 and dust) and waste water emissions. The waste waters from the process and the mining pits are let out into a dammed basin, formerly the natural Lake Kostomuksha. This basin flows north-east through several small lakes (e.g., Poppalijärvi, Kento) to the larger lake Middle Kuito and the White Sea. For these small lakes an exceptionally high mineral content, high pH value, and high concentrations of potassium, lithium and nitrogen in the water have been characteristic. However, the total phosphorus content (6–9 μg l−1) is slightly lower than in the Lake Upper Kuito (11–13 μg l−1) which acts as a reference lake. Biota from bacteria to fish were quantitatively sampled in August 2000 and 2001. Our results suggest a twice higher biomass of both phytoplankton (mainly picoalgae) and fish (biomass per unit effort) in the lakes downstream from the mine in comparison to the reference lake. Zooplankton and zoobenthos biomass both peak in L. Kento, the lake in the middle of the outflow series. The fish fauna (seven to eight species caught) is the same in all lakes and is dominated by perch and roach. Both grow well and roach show best growth in L. Poppalijärvi, next to the waste basin. Perch gills show some histopathological changes which do not, however, appear to affect either growth or reproduction.

The Kostomuksha Mining Plant in NW Russia (64• 30' N, 30• 30' E) extracts and processes iron ore into pellets (ca. 7 million t year-') for the meta! industry. The main environmental effects of the production operations are air pollution (70,000 t SO, year-') and wastewater emissions. The process and mining waters (ca. 3 million m year-') enter a 34-km' waste depository, dammed in 1982 from the former Lake Kostomuksha. The waters then seep into a lake-river system, which flows for ca. 250 km to the White Sea. The waste water contains high amounts of minerals, nitrogen and heavy metals. The depository has been reporred to overflow during spring floods; overfilling is also thought to increase the risk of dam breakdown. The aim of this srudy was to provide a general description of the chemistry and biology of two lakes below the mining plant, in comparison to a clean reference lake in the same catchment area. The main emphasis of the project was on the effects of pollution on fish populations and on individual fish (TKATCHEVA et al. 2000).

Toxicokinetics of 14 C-labeled bisphenol A (BPA) was studied in the small freshwater clam Pisidium amnicum at four ecologically relevant low temperatures (2, 6, 8, and 12°C). The uptake clearance ( k u ) of BPA increased from 1.49 to 6.55 ml · g −1 · h −1 as temperature increased from 2 to 8°C but decreased slightly again at the highest temperature. The depuration of BPA was very slow and statistically insignificant at 2°C, but the depuration rate ( k d ) increased linearly as temperature increased from 2 to 12°C. The longest half-life of BPA in clam tissues, 221 h, was found at the lowest temperature, and the highest bioconcentration factor of 144 was measured at 8°C. Data show that P. amnicum accumulates BPA so that the bioconcentration factor rises over 100 at each temperature tested. Further, the data demonstrate the importance of temperature on the processes that control both the uptake and elimination of this compound.

The community structure of littoral macroinvertebrates was explored by multivariate analyses in three basins of the large Lake Saimaa system (eastern Finland). The basins differed in trophic status and degree of human influence. It was hypothesized that the structure of littoral invertebrate communities is influenced by lake trophic status, as is the case in profundal communities. Three littoral habitat types with different substrate (stony, sandy and vegetated shores) were sampled from the shoreline to a depth of 1.5-3 meters. The habitat type was found to be largely determined by the slope of the shore and the wind exposure. Each habitat type supported fairly characteristic fauna, and detrended correspondence analysis grouped the invertebrate assemblages by habitat type rather than by basin. Within each habitat type, canonical correspondence analysis indicated that species composition changed along the trophic gradient. In the vegetated littoral zone, the greatest change in community structure occurred within the macrophyte beds, varying from the outer edge of macrophytes to the shoreline. Two alternative or complementary explanations are given for this horizontal gradient. First, a horizontal gradient of abiotic characteristics results in a change of community composition. Second, the macrophyte beds may form a horizontal transition zone in predation, from invertebrate predation inshore to fish predators offshore. On the stony and sandy shores, the magnitude of wave action was also important in structuring the communities. As each habitat type harbors characteristic fauna, a variety of habitats needs to be protected in order to conserve littoral macroinvertebrate diversity in large lakes. To make among-lake comparisons of littoral macroinvertebrate assemblages, stratification by habitat type is obviously necessary. The effects of eutrophication on invertebrate assemblages were most pronounced in stony habitats.

Seasonal variation in abiotic and biotic environments may modify the toxicity of organic chemicals for aquatic organisms. In present study, survival of the freshwater clam Pisidium amnicum was studied in laboratory exposures to pentachlorophenol (PCP) in April (at 5 degress C) and July (at 19 degress C). Behavioral responses, mean survival times (MSTs), and the lethal body burdens (LBBs) of PCP for uninfected clams and for clams infected by digenean trematodes were determined separately in two PCP concentrations, 100 and 300 microgram/L. Analysis of data revealed reduced behavioral activity of the clams in the PCP exposure compared to that in the control. The time needed for toxic responses was greatly affected by temperature; MSTs were 5 to 15 times longer in winter than at summer temperatures. Unexpectedly, the infected clams in summer were more tolerant to PCP than the uninfected clams. Despite the differences in survival times, the LBBs between the seasons were constant. However, in summer, the infected clams had significantly higher LBBs than the uninfected clams. The differences in survival and LBBs between the infected and uninfected clams are suggested to be caused by the high lipid contents found in parasites, which may change the internal distribution of PCP.