Inland Water Habitats Research Articles

Are all copepods the same? Variation in copepod stoichiometry with taxonomy, ontogeny, latitude, and habitat

AbstractCopepods are the most abundant metazoans on Earth, driving cycles of key elements in aquatic systems, most prominently carbon (C), nitrogen (N), and phosphorus (P). One key factor determining nutrient cycling is copepod somatic stoichiometry, which can reflect ecological strategy. We conducted a systematic review that updates the seminal work of Båmstedt (1986) by summarizing the effects of latitude, habitat, life history stage, and taxonomy on C:N, C:P, and N:P ratios of field‐collected copepods. We found that differences among copepod families accounted for the greatest variation, with the Rhincalanidae and Diaptomidae being particularly C‐rich, while the Calanidae were more N‐ and P‐rich. Copepod C:N was higher in inland waters compared with animals from marine environments in both copepodites and adult females, matching the higher C content of seston in many inland freshwaters. For both copepodites and adult females, mid‐latitude animals had higher C:N and C:P than high‐latitude animals, which matched predictions based on the availability of nutrients or adaptation to cold environments. More data must be gathered to fill gaps in our knowledge of copepod stoichiometry, focusing particularly on younger life stages, non‐calanoids, low and high latitudes, the southern hemisphere, and estuarine and some inland water habitats, including large lakes. Such information will help better parameterize models of aquatic ecosystems and improve our understanding of how copepods influence consumer‐driven nutrient cycling and food web dynamics.

Fatty acid profiles of migrating female silver eel from Mediterranean coastal lagoons as integrative descriptors of spawners biological quality

The present study analyzed the lipid content and fatty acid profiles of European silver eels from Mediterranean lagoons, to interrogate the ecology and biology of eel, a panmictic species well represented in the region, with particular reference to breeder quality. Lagoons are coastal waterbodies included in transitional waters, sharing with these ecosystems, that include also brackish wetlands and river mouths, the characteristic of being influenced both by sea and continental waters. In the Mediterranean area these highly productive ecosystems, that also support a rich specific biodiversity, have a great relevance in relation to their great extent and the human and historical dimension, since they have long been exploited for their natural resources, especially for fishing. Eel collection was carried out in nine Italian lagoons typically representing these habitats, and two inland water habitats (a river and a lake) were added for comparison. Female silver eel muscle tissue revealed a mean lipid content significantly above the threshold considered necessary to provide the cue to trigger physiological reproductive changes for this species, in all the sampling sites irrespective of their typology. This emphasises the importance of Mediterranean coastal lagoons as habitats contributing to the eel oceanic migration, providing a significant share of spawning-stock biomass, both in terms of quality of the breeders and of their fitness to perform migration. Whereas the overall lipid content was similar among sites, the nine local populations differed in their fatty acid signatures. Thus, FA signatures might be proposed as integrative descriptors of eel spawner biological quality since they easily are able to differentiate among silver eel local stocks. Growth rates and body condition indices were strongly positively correlated to n-3:n-6 and DHA:EPA ratios in silver eels ready-to-migrate from the studied locations. This demonstrates that distinct PUFA, exclusively obtained through diet, are correlated with crucial biological features such as growth and condition of the silver eels that are going to undertake their journey to their oceanic reproduction sites. Overall, our results show the importance of additional tools for evaluating eel breeder quality that could also be integrated in the overall assessment of local stocks, a crucial step for ongoing and further management strategies of this endangered species.

Financing biodiversity conservation

Biodiversity Global funds for protecting biodiversity are too low to prevent wildlife populations from falling and species extinctions from increasing. In a Perspective, Barbier et al. call for a global agreement for biodiversity modeled on the Paris Climate Agreement, with national targets, policies, and timelines. The overall goal is ambitious: to conserve at least 50% of terrestrial, inland water, coastal, and marine habitats by 2050. Formal involvement of the private sector, particularly in areas such as seafood, forestry, agriculture, and insurance, will be crucial to raise the necessary funds. Science , this issue p. [486][1] [1]: /lookup/doi/10.1126/science.aar3454

Contamination of fish in UK fresh water systems: Risk assessment for human consumption

There is growing evidence that more people in the UK are consuming fish taken from inland waterways. This may be partly due to the increased numbers of migrants from Eastern Europe where this is part of traditional culture and partly because of a desire to try new foods encouraged by celebrity chefs. Fish can bioaccumulate environmental contaminants and so could contribute a significant amount to dietary exposure to these chemicals. This study examined the changing habits of anglers and consumers and characterised a range of existing and emerging contaminants in freshwater fish species with a view to determining current levels of occurrence and possible risk from consumption. The project was conducted in two stages. The first stage included (a) a study that identified freshwater systems that are contaminated either by anthropogenic activity or as a result of the geology of the area; and (b) socioeconomic research to assess the consumption habits of the public, particularly anglers, with respect to fish and shellfish from unmanaged inland waterways. Based on the outcome from the first stage, specific rivers and other inland waterways were chosen for investigation, along with the range of contaminants to be included in the analytical programme. Predicted contamination levels and prevalence of anglers were among the factors taken into consideration.The second stage of the project involved sampling and analysis of fish taken from selected locations on the chosen waterways. A range of fish species from a variety of inland water habitats were obtained. These were analysed for the following contaminants: heavy metals, chlorinated dioxins (PCDD/Fs), polybrominated biphenyls (PBBs), polychlorinated biphenyls (PCBs), brominated dioxins (PBDD/Fs), polychlorinated naphthalenes (PCNs), polybrominated diphenylethers (PBDEs), OC pesticides, organotin compounds and organo-fluorine compounds.Legal limits for contaminants apply only to food traded commercially, but some samples were in excess of the regulatory limits for PCDD/Fs and PCBs in such fish. The maximum detected WHO-TEQ (1998) for PCDD/Fs plus PCBs was over 32ngkg−1 on a whole weight basis for a sample of barbel from the River Don, and 6 other samples were also above the 8ngkg−1 limit.

Natura 2000 habitats in Tuscany (central Italy): synthesis of main conservation features based on a comprehensive database

We analyse and report a synthesis of a long-term project leading to the creation of a database of habitats of conservation interest in Tuscany (Italy). All available floristic and vegetation literature from 1960 to date and relating to the Tuscan territory, and all terrestrial and inland water (non-marine) Habitats of European Community Interest as listed in Annex I of the EU Habitats Directive present in Tuscany have been identified and taken into account. A total of 2,691 sites were attributed to 82 different conservation interest habitat types and were geo-localised and uploaded to the database. For each habitat site, threat and pressure factors are indicated and a quick expert-based assessment made on the basis of three parameters: rarity, vulnerability and a quality estimate. For the analysis, all database information was referred to a vectorial 10 × 10 km grid. The territorial distribution of habitats is discussed with respect to: the level of information available, the numbers of reports and the habitat-type concentration. The major threats and pressures affecting these Tuscan habitats are highlighted and discussed. Vegetation dynamics proved to be the most important natural/seminatural threat. Another important threat is invasion by/competition with other organisms, mainly invasive alien species. Among anthropic threats, the management of riparian and aquatic vegetation together with water management all strongly affect many habitat types with links to wetlands. Infrastructures, particularly those connected with tourism and recreation, are an important threat factor especially in coastal areas. Some positive effects of certain anthropic pressures are also illustrated. Lastly, some actions to improve habitat knowledge, evaluation and conservation are suggested.

Hematological alterations induced by phenol exposure in Oncorhynchus mykiss

In the present study, the impacts of phenol, a pollutant of inland water habitats, were investigated on Oncorhynchus mykiss. The fish (weight = 300 ± 7.5 g, total length = 18.58 ± 3.8 cm) were subjected to 0.6, 1.2, and 2.4 mg/l of phenol concentration for 8 weeks. At the end of study, blood samples were taken via cardiac puncture by heparinized syringes, and hematological assays were done by standard methods. Red blood cell counts, hematocrit, hemoglobin concentration, and mean corpuscular hemoglobin concentration value decreased after phenol exposure while white blood cells counts showed an increase. The values of mean corpuscular hemoglobin and mean corpuscular volume were not affected by phenol treatment. Our findings showed that hematological parameters can be used as diagnostic indices to evaluate the health status of O. mykiss after exposure to phenol.

Implications of climate change for the reproductive capacity and survival of New World silversides (family Atherinopsidae)

The New World silversides (family Atherinopsidae) are found in marine, estuarine and inland waters of North, Central and South America, where they are ecologically important as forage fishes and sometimes economically important for commercial and recreational fisheries. This report reviews the knowledge of the reproductive attributes of temperate and subtropical atherinopsids in relation to temperature and discusses the potential effects of climate change on their reproduction and adaptive responses. Their reproductive cycles are primarily entrained by photoperiod with high temperature acting as a limiting factor. They are generally multiple spawners which release successive batches of eggs in spring, but some species can spawn also in autumn and even summer when temperatures do not increase excessively. The decoupling of temperature patterns and photoperiod with further global warming and associated asymmetric thermal fluctuations could lead to spawning at times or temperatures that are unsuitable for larval development and growth. Many members of this family show temperature-dependent sex determination (TSD), where the phenotypic sex of an individual is determined partly or wholly by the temperature experienced during gonadal sex differentiation, and high-temperature induced germ cell degeneration and decreased fertility. The predicted short-term reproductive responses of atherinopsids to climate change therefore include acceleration, shortening or overall disruption of spawning activity, and also more subtle, but nonetheless equally population-threatening, dysfunctions such as highly skewed sex ratios and partial or total loss of fertility. In the case of species with TSD, asymmetric thermal fluctuations could also cause larvae to encounter temperatures lower than normal during early development and be feminized. Such dysfunctions have been documented already in natural populations but are confined so far to landlocked, inland water habitats, perhaps because they impose more severe thermal fluctuations and limitations to migration and dispersal. The severity and recurrence of these dysfunctions with further climate change will depend both on the magnitude, speed and pattern of change and on how much (or how fast) physiological and behavioural traits can evolve to match the new conditions imposed by the climate, which is largely unknown. In this regard, compelling evidence is shown that numerous traits, including the sex determination system, are capable of rapid evolution and could mitigate the negative effects of temperature increases on population viability in atherinopsids.

The allochthonous component in the fauna of peninsular Italy

Biogeographia vol. XX VII - 2006 (Pubblicato il 30 dicembre 2006) Biogeografia del/’Appennino centrale e sertentrionale.‘ trent’anni dopo The allochthonous component in the fauna of peninsular Italy MARZIO ZAPPAROLI Dzpzzrriivzenro di Prarezimze zlelle Pizlnte, Um'z2er5z'tz‘z degli Stzzdi della 72155222, Via 5471 C. De Lellis s.7z.c., 01100 Viterbo (Italy); e—mzzz'/.' zzzppmqo[@zmz'tzz5. it Key words: Italy, introduced species, biological invasions SUMMARY A broad picture of the animal species, both terrestrial and inland water, that have recently been introduced in the Apennine region of Italy (from Tuscany to Calabria) is presented in this paper. Information was gathered from a) the latest studies on the consistency and distribution of the Italian fauna (e.g., “Checklist delle specie” and “Clemap” projects), b) syntheses on particular taxonomic groups and/or fields of research, and c) other information from scientific literature or from taxonomists. Extinct allochthonous species, species whose status of acclimatizationl naturalization is unknown, and patautochthonous species (introduced before 1500 A.D.), were excluded from this analysis. 397 allochthonous species have been documented as introduced in this area, of which 320 (80.6%) have naturalized (represented by self- sustaining populations) and 77 (19.4%) have acclimatized (with populations in the wild, but not yet self sustaining). The naturalized species constitute 1.2°/o of the fauna in the study area (26,200 total species). The majority of introduced species are Arthropoda, in particular lnsecta (68% of the naturalized species, especially Homoptera Sternorrhyncha and Coleoptera), followed by Vertebrata (16% of the naturalized species, especially Osteichthyes). Annelida Oligochaeta, Mollusca Gastropoda and Bivalvia, Platyhelminthes and Nematoda are also present, but are much less numerous. According to the presence/ absence regional data of 189 introduced species (both acclimatized and naturalized), Lazio, Tuscany and Campania are the surveyed administrative regions in which the highest number of species have been recorded. This result could be due to a greater effort of research having been realized in these areas or to the presence of factors that “predispose‘’ the entry of allochthonous species, such as the high number of city centers, economic activities, and anthropic disturbance. Witli regard to the causes of introduction, the unintentionally introduced species represent 75% (304 species), while the intentional introductions represent only 25% (93 species) of the total; in both categories the naturalized species constitute 75-80%. Intentional introductions were carried out for biological control (34%), professional and sport fishing (27%), collection/ornamental (18%), hunting/alimentary (12%), industrial (fur and other) (4%) and scientific (3%) purposes. The unintentional introductions occurred largely through the importation of plants and/or vegetable products (58%), human movements (17%), importation of stored products (11.5%), fish spawning/aquaculture (5.5%), and importation of infected animals (2%) or other (4%). According to the zoogeographic origin of 298 introduced species, 44% are of Palaearctic (16% E-Palaeatctic, 28% W-Palaearctic), 21% Neoarctic, 11% Afrotropical, 10% Neotropical, 9% Oriental, 6% Australoasiatic origin. A preliminary assessment based on the presence and distribution in selected macrohabitats of potentially or efl-ectively invasive (impacting on biodiversity) species suggest that natural inland water habitats are at greater risk of invasion in comparison with natural/semi—natural terrestrial ones. However differing amounts of knowledge are available for the two main type of habitats, greater for the inland water, smaller for the terrestrial ones. In the latter, the effects produced by allochthonous mammals and birds are especially known, meanwhile information about the impact of introduced invertebrates is highly laclting, in particular of insects, which While represented in great numbers of species are at present largely confined to artificial habitats (urban areas and/ or agroecosystems).

Identifying important sites for conservation of freshwater biodiversity: extending the species‐based approach

Abstract Species richness in relation to area of habitat is extremely high in many freshwater groups, with an estimated 12 000 fish, 5000 amphibians and 2000 mollusc species dependent on freshwater habitats. Other major groups dependent upon fresh waters include, reptiles, insects, plants and mammals. The IUCN Redlist and The Nature Conservancy assessments both indicate the serious vulnerability and degradation of inland water habitats world‐wide. It is evident that there are neither the resources nor the time to protect all areas where species are under threat. Clearly a method is needed for prioritising inland water sites for conservation at both local and regional scales. IUCN held a workshop in June 2002 to develop a method for prioritising important inland water sites for biodiversity conservation. The goal of the workshop was to develop a method which would help to focus on conservation efforts and funds at the regional scale and would serve as a tool for active conservation efforts at the local scale. The method was developed on the foundations of a review of the existing site prioritisation schemes for terrestrial, marine and freshwater ecosystems. Expert representatives for a broad range of priority taxa and for existing schemes provided input to the development of the site prioritisation method. This paper describes the development of the method, the selection criteria adopted, guidelines for their use and the site selection procedure.

Current status of the threatened amphibians and reptiles of Japan

AbstractThis article compares amphibian and reptile components of the original and revised versions of the Red List of Japan, and analyzes geographic patterns of, and major threats to, species and subspecies now assigned to the threatened categories. The numbers of both amphibians and reptiles categorized as threatened in the Red List of Japan have increased greatly through its revision as a result of recent progress in the taxonomy of these groups in Japan, the introduction of new criteria for risk assessment, and unexpectedly rapid declines in the status of several taxa. Threatened taxa of amphibians and reptiles in the revised list tend to be concentrated in the Ryukyu Archipelago, where deforestation seems to be the major ultimate cause of declines. Reduction in the quality and quantity of inland water environments seems to be the major cause of declines in several endemic amphibians from the main islands of Japan. The importance of conservation was emphasized in the revised list by progress in taxonomy, by new insights and data on the estimation of temporal dynamics of population density or habitat size for threatened taxa, and by the impacts of and need to prevent further deforestation in the Ryukyus and of the ongoing destruction of inland water habitats on the main islands of Japan.

First record ofBranchinella spinosa (Milne-Edwards) (Crustacea: Branchiopoda: Anostraca) from Greece

As the result of a first screening of temporary inland water habitats,Branchinella spinosa is here recorded for the first time in Greece. This finding extends the circum-Mediterranean part of its vast distribution. The species was collected from a shallow astatic coastal salt-marsh that is mainly fed by rainwater, where it coexists but rarely co-occurs withArtemia parthenogenetica. Branchinella spinosa is only the fourth anostracan species currently known from Greece. The poor knowledge of anostracan richness and abundance is mainly due to limited sampling efforts in this area. As temporary aquatic habitats are threatened by several anthropogenic activities, especially agriculture and land clearing for urbanisation and tourism, there is an urgent necessity for further monitoring and protection of these precious habitats.

First record of Branchinella spinosa (Milne-Edwards) (Crustacea: Branchiopodacolon; Anostraca) from Greece

As the result of a first screening of temporary inlandwater habitats, Branchinella spinosa is hererecorded for the first time in Greece. This findingextends the circum-Mediterranean part of its vastdistribution. The species was collected from a shallowastatic coastal salt-marsh that is mainly fed byrainwater, where it coexists but rarely co-occurs withArtemia parthenogenetica. Branchinellaspinosa is only the fourth anostracan speciescurrently known from Greece. The poor knowledge ofanostracan richness and abundance is mainly due tolimited sampling efforts in this area. As temporaryaquatic habitats are threatened by severalanthropogenic activities, especially agriculture andland clearing for urbanisation and tourism, there isan urgent necessity for further monitoring andprotection of these precious habitats.

Larval development of the crab Cancer magister in temperature regimes simulating outer-coast and inland-water habitats

Larval development of the crab Cancer magister in temperature regimes simulating outer-coast and inland-water habitats

Maternal control of calcium concentration in the larval nursery of the bromeliad crab,Metopaulias depressus(Grapsidae)

It has been proposed that parental care in invertebrates controls for physicochemical conditions. This suggests that the parent detects deviations from optimal conditions and responds by correcting the deviation for the benefit of the offspring. In the bromeliad crab, Metopaulias depressus, mothers accumulate snail shells (CaCO3) in the leaf axil containing the larvae, which results in an increase in Ca2+ and pH, both beneficial to the young. I tested the hypotheses that mothers: (i) control for calcium levels and only collect shells when calcium is too low; (ii) always collect shells, independent of the calcium content of the nursery; (iii) collect shells if encountered, but increase their activity if the calcium content becomes critical. In a field experiment, I reduced the initial calcium concentration in the nurseries of one group and increased it in another group. In both groups mothers collected shells. However, they collected significantly more shell mass per day in the group with reduced levels than in the group with high levels. The results support hypothesis (iii) and unequivocally demonstrate maternal control of physicochemical conditions in the nursery. This is the first proof that crustacean mothers actively regulate abiotic conditions for their offspring.

Larval development of the crabCancer magister in temperature regimes simulating outer-coast and inland-water habitats

Postlarval megalopae of the Dungeness crabCancer magister inhabiting offshore coastal waters along the west toast of North America are larger and settle earlier than do those occupying the inland waters of the Puget Sound basin (Washington, USA, and British Columbia, Canada). The Puget Sound habitat is characterized by low initial temperatures that steadily increase during the course of zoeal development, while offshore temperatures are more moderate and stable. Larvae were raised in the laboratory from hatching to megalopa in three temperature treatments: (1) constant 10 °C (CO), (2) a regime that temporally simulated temperatures found off the central California coast during the larval season (CA); and (3) a regime simulating temperatures found within the Puget Sound basin (PS). Zoeal duration was 44% longer in the PS treatment than in the other two, at least partially accounting for observed differentes between outer-toast and inland-water settlement times. Although differentes were measured in megalopal weights and carapace lengths among treatments, results do not explain differences in megalopal size observed between outer-toast and inland-water individuals. Survival to megalopa was highest in the PS treatment, with the difference due to significantly lower mortality than in CO and CA treatments during the terminal zoeal stage. Daily instantaneous mortality rates were lower in the PS than in CO or CA treatments, indicating Chat extended larval duration will not necessarily result in reduced settlement success.

Temporal salinity variation in salt evaporation basins in south-eastern Australia

Salt evaporation basins in south-eastern Australia, in contrast with natural saline lakes in this region, were not highly saline and exhibited little seasonal pattern in water depth and salinity over a 2-year sampling period. Lack of seasonality arose from either constant inflow (from continuous groundwater pumping) or erratic inflow (from unpredictable irrigation demands). Differences in zooplankton species composition between the salt evaporation basins and natural saline lakes might reflect the differences in temporal salinity patterns. Some typical saline lake zooplankton were not found in the evaporation basins. Salt evaporation basins therefore may represent additions to the inland water habitats of semi-arid Australia.

Fossilization of feathers

Scanning electron microscopy of feathers has revealed evidence that a bacterial glycocalyx (a network of exocellular polysaccharide fibers) played a role in promoting their fossilization in some cases. This mode of preservation has not been reported in other soft tissues. The majority of fossil feathers are preserved as carbonized traces. More rarely, bacteria on the surface are replicated by authigenic minerals (bacterial autolithification). The feathers of Archaeopteryx are preserved mainly by imprintation following early lithification of the substrate and decay of the feather. Lacustrine settings provide the most important taphonomic window for feather preservation. Preservation in terrestrial and normal-marine settings involves very different processes (in amber and in authigenically mineralized coprolites, respectively). Therefore, there may be a significant bias in the avian fossil record in favor of inland water habitats.