Faunal Changes Research Articles

Effects of Land-Use Change on the Community Structure of the Dung Beetle (Scarabaeinae) in an Altered Ecosystem in Southern Ecuador.

Simple SummaryThis study analyzed the abundance and diversity of dung beetle communities at several disturbed sites in a tropical dry forest ecosystem in southern Ecuador. Dung beetle community diversity indices with different land uses were related to environmental variables (altitude, temperature), soil physicochemical properties, and food supply (manure). The results indicated that the species Canthon balteatus, Dichotomius problematicus, and Onthophagus confusus are abundant in disturbed sites, where soils are generally more compact and less fertile but contain a greater food supply. These findings can help decision makers to identify disturbed areas and to implement adequate policies for sustainable environmental management.This study evaluated the effects of land-use change (L-UCH) on dung beetle community structure (Scarabaeinae) in a disturbed dry ecosystem in southern Ecuador. Five different L-UCH classes were analyzed by capturing the dung beetle species at each site using 120 pitfall traps in total. To determine dung beetle abundance and diversity at each L-UCH, a general linear model (GLM) and a redundancy analysis (RDA) were applied, which correlated environmental and edaphic conditions to the community structure. Furthermore, changes in dung-producing vertebrate fauna were examined, which varied significantly between the different L-UCH classes due to the specific anthropogenic use or level of ecosystem disturbance. The results indicated that soil organic matter, pH, potassium, and phosphorus (RDA: component 1), as well as temperature and altitude (RDA: component 2) significantly affect the abundance of beetles (GLM: p value < 0.001), besides the food availability (dung). The highest abundance and diversity (Simpson’s index > 0.4, Shannon-Wiener index > 1.10) was found in highly disturbed sites, where soils were generally more compacted, but with a greater food supply due to the introduced farm animals. At highly disturbed sites, the species Canthon balteatus, Dichotomius problematicus, and Onthphagus confuses were found specifically, which makes them useful as bio-indicators for disturbed dry forest ecosystems in southern Ecuador.

Climate shifts vs. edaphic humidity and the difficulty of palaeoreconstructions – a malacological study on stable isotopes in Quaternary dune sequences of Fuerteventura

ABSTRACTDune palaeosurface sequences on the Eastern Canary Islands were investigated for stable isotope records in gastropod shells of the genus Theba. Due to the ecology of the taxon and the special oceanic insularity of the study site, we assume that δ18Oshell signals in our case mainly reflect shifts in δ18O signals of sea surface water. We found that a rapid decrease in δ18Oshell signals is associated with significant changes in gastropod associations. We suggest that these faunal changes were caused by strong (hot) winds at the end of glacial phases, that were described previously by Moreno et al. In addition, we assume that rapid declines in δ18Oshell signals due to marine transgressions were followed by geomorphologically stable phases, dominated by dust enrichment. Such palaeosurfaces correlate with maxima of gastropod biodiversity and with more negative δ13Cshell signals indicating a higher proportion of C3 plants. Based on our results, we also assume that these silty palaeosurfaces were associated with increased soil moisture conditions due to a higher water storage capacity of the finer substrate, independent of climatic moisture conditions.

Determinants of fish distribution pattern and habitat preference in protected Karaj River, Iran

Lack of information about ichthyofauna makes it difficult to predict human effects on the communities. In this study, the effects of the environmental and human factors were examined on altitudinal patterns of fish habitat selection, faunal changes, species richness and fish abundance from upstream to downstream in the southern part of the central Alborz Protected Area during 2016 and 2017. 366 fish individuals of five species in three families were identified and brown trout was the dominant species. The river was divided into three zones based on habitat structure, species composition and influence of physical and chemical variables. The results indicate that, in some situations, including small changes in habitat structure indices, physical and chemical variables along the altitudinal gradient are more effective in habitat preference, describing the composition, and abundance. Chemical variables can help to have a better understanding of the conventional patterns, shaped by the habitat structure and physical variables. Habitat suitability index model for brown trout in three zones is completely different over the two years and this species could overcome these conditions. However, upstream areas were more appropriate. Dam, with decreases of outlet water temperature, also creates homogeneous and simple habitats leading to changes in expected fish distribution patterns with decreasing altitude. These conditions may have increased habitat suitability index for the brown trout in downstream, while despite favorable ecological conditions in the middle zone, habitat suitability index and alternative habitats available in this zone are likely to decline due to density and interspecific competition. The natural pattern of fish distribution and habitat selection varies along the altitudinal gradient due to various factors and human disturbances. Optimal management of protected areas can control the effects of some of these factors at least temporarily.

Environmental triggers of faunal changes revealed by benthic foraminiferal monitoring

Benthic foraminifera are deemed sensitive indicators of environmental conditions. Triggers and magnitudes of faunal response to environmental changes are yet poorly constrained. Benthic foraminiferal faunas were monitored annually at Ria Formosa (Algarve, Portugal) coastal lagoon since 2013. Distinct environmental changes were recognised during the monitoring period. The relocation of a tidal inlet in winter 2015 effected faster flushing, higher tidal levels, and stronger currents in the Esteiro do Ancão tidal channel. The epibenthic foraminiferal species Asterigerinata mamilla increased in abundance and the population densities of the whole fauna were double as high as before inlet relocation. Enhanced sediment redeposition was recorded and extensive polychaete colonies successively replaced firmground patches with oysters. The standing stock of the foraminiferal fauna declined in the next year due to food impoverishment, while the high hydraulic energy levels and high percentages of Asterigerinata mamilla maintained. Benthic foraminifera responded much faster to environmental perturbations than macroorganisms identifying them as powerful proxies in environmental studies.

Arthropodofauna richness and abundance across beach–dune systems with contrasting morphodynamics

The across-shore distribution of arthropods in two Uruguayan sandy beach–dune​ systems with contrasting morphodynamics was investigated. A deconstructive analysis was performed to describe faunal changes from the dunes to the shoreline. The Habitat Safety Hypothesis (HSH), which states that sandy beach supralittoral species are more abundant in the backshore of reflective beaches than in dissipative ones, was assessed. A hypothesis that predicts more diverse and abundant supralittoral and dune insects and arachnids in dissipative beaches was also tested. Sampling was performed simultaneously in both beaches with pitfall traps that were kept active for 24 h at three transects that included 17 sampling levels. The reflective beach presented significantly higher elevation, sand temperature, grain size and sorting, and lower sediment compaction and moisture than the dissipative one. Total abundance of arthropods was significantly higher in the reflective beach, supporting the HSH. However, the deconstructive analysis revealed different patterns in the across-shore distribution, diversity and abundance among taxa. Crustaceans, coleopterans and dipterans exhibited higher abundance in the backshore of the reflective beach, whereas acarines were more abundant in the dunes of the dissipative beach. Ants were similarly abundant in the dunes of both beach types. Species diversity did not differ between beaches and was higher in the dunes than in the backshore. The higher abundance observed in the backshore of the reflective beach supports the HSH, reinforcing the idea that the backshore of reflective beaches can be a safer zone not only for beach crustaceans inhabiting this beach fringe, but also for some insects (coleopterans and dipterans). Other arthropods (acarines) inhabiting the dunes were more abundant in the dissipative beach. The similar abundance of ants found in both beaches suggests that dunes offer suitable microhabitats for them, overriding the effects of beach morphodynamic factors.

Reduced Efficacy of Fenbendazole and Pyrantel Pamoate Treatments against Intestinal Nematodes of Stud and Performance Horses.

Nematodes are an important cause of disease and loss of performance in horses. Changes in the parasitic fauna of horses have occurred in the past few decades, making cyathostomins the major parasites in adult horses, while large strongyles have become less prevalent. Parascaris spp. remains the most important parasite infecting foals and weanlings. Anthelmintic resistance is highly prevalent in cyathostomins and Parascaris spp. worldwide and it must be factored into treatment decisions. To assess anthelmintic efficacy in Northern Italy, we sampled 215 horses from 17 sport and horse-breeding farms. Fecal egg count reduction tests (FECRT) were used to assess anthelmintic efficacy. Copromicroscopic analysis was performed using MiniFLOTAC before treatment with fenbendazole, pyrantel pamoate or ivermectin, and repeated 14 days post-treatment. Strongyle-type eggs were detected in 66.91% of horses (CI95% 61.40–73.79%), while Parascaris spp. was detected in 2.79% (CI95% 1.94–5.95%). Reduced efficacy against cyathostomins was observed for fenbendazole in 55.56% of the treated animals (CI95% 41.18–69.06%), and for pyrantel pamoate in 75% of animals (CI95% 30.06–95.44%). Ground-based actions must be set in place to promote the uptake of state-of-the-art worm control plans that will prevent clinical disease while minimizing the selection pressure of resistant parasites.

Crab Diets Differ Between Adjacent Estuaries and Habitats Within a Sheltered Marine Embayment

Portunid crabs contribute to significant commercial and recreational fisheries globally and are commonly fished in estuaries and/or marine embayments, which are amongst the most degraded of all aquatic ecosystems. Portunus armatus were collected seasonally between April and February from five locations across three systems in temperate south-western Australia. The dietary composition of crabs was quantified and compared between two estuaries (Peel-Harvey and Swan-Canning) and a sheltered marine embayment (Cockburn Sound) containing three distinct habitats: shallow seagrass, shallow sand and deep sand. Overall, crabs ingested large volumes of bivalves (both live organisms and dead shell), polychaetes, crustaceans (e.g., amphipods, small decapods), and smaller volumes of teleosts, echinoderms and plant material (seagrass, algae). Analysis of Similarities showed that dietary composition varied significantly among the five locations (two estuaries and three habitats within Cockburn Sound) and seasons, with greater location than seasonal differences in the two estuaries. Diets were most distinct in the Cockburn Sound seagrass due to greater volumes of decapods and teleosts and smaller volumes of bivalve shell consumed in this habitat. Crabs from both estuaries consumed greater quantities of bivalves than those from Cockburn Sound. Seasonal differences in both estuaries were greatest between summer and winter, with a more diverse range of prey and large quantities of bivalves ingested in summer, whereas small bivalves and bivalve shell in the Peel-Harvey and polychaetes and other crustaceans in the Swan-Canning, were consumed in greater quantities in winter. The summer diet in the Peel-Harvey Estuary in the current study was compared to that 20 years previous and with documented change in the benthic macroinvertebrate fauna. Currently, crabs consume smaller volumes of high-calorie prey, i.e., polychaetes, small bivalves and teleosts, and instead ingest greater proportions of calcareous material than previously. This marked shift in dietary composition parallels changes in benthic macroinvertebrates in the Peel-Harvey Estuary. Overall, prey availability appears to be the major factor influencing the spatial and temporal differences in P. armatus diets in these three coastal systems.

The First 40 Million Years of Planktonic Foraminifera

We provide a biochronology of Jurassic planktonic foramininfera, using first order linkage to ammonite and nannofossil stratigraphy and geochronology. This enigmatic and understudied group of microfossils occurred from middle Toarcian through Tithonian time, from ~180 to ~143 Ma; its origin is unknown. There are three genera: Globuligerina, Conoglobigerina and Petaloglobigerina. The genus Globuligerina, with a smooth to pustulose test surface texture appeared in Toarcian (late Early Jurassic) and Conoglobigerina, with a rough reticulate test surface texture in Oxfordian (early Late Jurassic) time. The genus Petaloglobigerina, having a petaloid last whorl with one or more claviform and twisted chambers evolved in early Kimmeridgian time from Globuligerina balakhmatovae. Biochronologic events for Jurassic planktonic foraminifera are most like First Common Appearance or Last Common Appearance events. The very first or very last appearance levels of taxa are not easily sampled and detected. We recognize stratigraphic events from eleven species across four postulated evolutionary lineages, calibrated to Geologic Time Scale 2020. A faunal change, which is not well documented led to the survival of only one taxon, most likely Gobuligerina oxfordiana in the Tithonian.

Middle Miocene platform drowning in the Maldives associated with monsoon-related intensification of currents

The partial drowning of the Mid-Miocene Kardiva Platform in the Maldives occurred at 13 Ma in the northern Kardiva Channel and at 10.6 Ma in the southern Kardiva Channel. The 13 Ma drowning coincided with the onset of the monsoon-driven currents in the Indian Ocean. The drowning had previously been explained as a consequence of current-induced upwelling and the resultant injection of nutrients into the surface waters and expansion of the oxygen minimum zone (OMZ). However, cores retrieved during IODP Expedition 359 across the drowning successions on the platform and its slope, into the overlying contourite drifts, do not display any of the faunal changes usually associated with such an environmental change.Here we use the δ15N values of sedimentary organic material and the improved total phosphate analysis as geochemical proxies for nutrients and total organic carbon (TOC) as an indicator for ocean anoxia to investigate the causes of platform drowning. This produced two important results, (1) both nutrient proxies, δ15NOM and total phosphate (TPO4) remain unchanged across the drowning successions and into the drift successions, indicating that the nutrient content on the platform and in the Inner Sea did not increase prior or during platform drowning, and (2) little to no TOC is preserved in the drowning successions, providing evidence that the expanding OMZ did not result in ocean anoxia, which could have aided in the demise of the platform. An increase in nutrient content (δ15NOM) is found at 11 Ma, about 2 Myr after the drowning of the Kardiva Platform in the mid-Miocene. Therefore, neither current-induced nutrient injection nor an expansion of the OMZ can be implicated in the platform drowning. Instead, the onset of strong currents seems likely to be the primary cause of the partial platform drowning. A mechanism is envisioned in which flooding of the previously exposed platform is coupled with the onset of a strong current that sweeps the platform of newly produced sediment and inhibits coral larvae settlement.

Pollination strategies in the face of pollinator decline

ABSTRACT The recent pollinator decline in developed countries has been documented in many parts of the world and its anthropogenic causes are now identified. Because pollinators contribute to the sexual reproduction of many plant species, pollinator decline constitutes a potential threat on insect-pollinated plant populations. Moreover, it is susceptible to impede pollination services to crops in agriculture. In this paper, I review the empirical evidence that pollinator decline translates (or not) into pollen limitation for plants and alters plant-pollinator networks. I also analyse the possibility of short-term evolution of plant pollination strategies. In particular, I discuss how changes in pollinator fauna constitute new selection pressures for plants and how plant reproductive traits are able to respond rapidly to such new selection regime. Mating system evolutionary theory thus predicts that short-term evolution may allow plant populations to adapt to pollinator decline, potentially rescuing populations, as predicted by the evolutionary rescue theory. Nevertheless, mating system theory and empirical data support the idea that evolutionary rescue through mating system adaptation is not always possible. Finally, I discuss how plant evolution may disturb plant-pollinator interactions potentially breaking major trophic links in ecosystems, which could in turn reinforce pollinator’s extinction in the future.

Long-Term Empirical Studies Highlight Multiple Drivers of Temporal Change in Bird Fauna in the Wet Forests of Victoria, South-Eastern Australia

Birds are high profile elements of the vertebrate biota in almost all terrestrial ecosystems worldwide. Many studies have uncovered evidence of a decline in bird biodiversity, but temporal patterns of change vary among ecosystems and among bird species with different life history traits. Ecosystem-specific, long-term studies are critical for identifying patterns of temporal change in bird biodiversity and the drivers of that change. Here we present a case study of drivers of temporal change in the bird fauna of the Mountain Ash and Alpine Ash eucalypt forests of south-eastern Australia. Using insights from observational studies and experiments conducted over the past 18 years, we discuss the direct and interactive effects of fire and logging on birds. The extent and severity of wildfires have major negative effects on almost all bird species, and have persisted for more than a decade after the last major conflagration (in 2009). Logging has markedly different effects on birds than those quantified for fire, and may have resulted in elevated levels of site occupancy in remaining uncut areas in the landscape. Both fire and logging have led to marked losses in the extent of old growth forest in Mountain Ash and Alpine Ash ecosystems. This is a concern given the strong association of most species of birds with old forest relative to younger age cohorts. Based on an understanding of the effects of fire and logging as drivers of change, we propose a series of inter-related management actions designed to enhance the conservation of avifauna in Mountain Ash and Alpine Ash ecosystems. A particular focus of management must be on increasing the interval between fires and limiting the spatial extent of wildfires and, in turn, significantly expanding the extent of old growth forest. This is because old growth forest is where most bird species are most likely to occur, and in the event of future wildfires, where fire severity will be lowest. Expansion of the old growth estate will require commercial logging operations to be excluded from large parts of Mountain Ash and Alpine Ash forests.

Recent environmental change in the Kosterhavet National Park marine protected area as reflected by hydrography and sediment proxy data

The Koster Trench is the deepest part of the Kosterfjord (Skagerrak, North Sea), which stretches southward along the west coast of Sweden. Since 2009 Kosterfjord has been included in the Marine Protected Area Kosterhavet National Park. To effectively manage national parks, long-term time series of ecological data are needed and those can be derived from local sediment archives. In this study we present multiproxy geochemical (bulk TOC, C/N and heavy metals) and micropaleontological (dinoflagellate cysts, selected palynomorphs and benthic foraminifera) data from a sediment core taken in the southern part of the Koster Trench. Radiometric dating by 210Pb and 137Cs shows that the core archived the environmental changes that took place between 1988 and 2012. The TOC, heavy metals and foraminiferal indices indicate mainly high to good Ecological Quality Status, with moderate ecological quality for arsenic concentrations. Dinoflagellate cysts suggest a major change occurring in the upper water column around 2002. The cysts of Pentapharsodinium dalei peak around 1992 and show overall slightly higher relative abundances between 1988 and 2002. Increased abundance of Biecheleria baltica cysts, heterotrophic species, oligotrichids, pollen and spores characterise the upper core part deposited from 2002 to 2012. Also, there is a clear increase of Alexandrium cysts in the top of the core (~2008–2012). Benthic foraminifera show a major faunal change reflected in a significant increase of agglutinated species (mainly Textularia earlandi) from 2007 towards present day, while the lower part of the core (1988–2007) is dominated by calcareous species. Overall, the changes demonstrated by the dataset suggest an increased freshwater input or a higher river/land runoff, as supported by climatic and hydrographical data showing increased precipitation over the study area, decreasing salinity, and an increasing trend in particulate organic carbon in the surface waters. These changes, in combination with trawling activities, which have been moved to the deepest part of the trench since 2009, seem to favour dinoflagellate and benthic foraminiferal species with mixotrophic and omnivorous feeding strategies. Similar to the dinocysts, calculated foram-AMBI and NQIforam indices show a shift around 2002 suggesting that environmental changes occurring in the study area are likely linked to darkening of coastal waters.

The Eocene–Oligocene transition: a review of marine and terrestrial proxy data, models and model–data comparisons

Abstract. The Eocene–Oligocene transition (EOT) was a climate shift from a largely ice-free greenhouse world to an icehouse climate, involving the first major glaciation of Antarctica and global cooling occurring ∼34 million years ago (Ma) and lasting ∼790 kyr. The change is marked by a global shift in deep-sea δ18O representing a combination of deep-ocean cooling and growth in land ice volume. At the same time, multiple independent proxies for ocean temperature indicate sea surface cooling, and major changes in global fauna and flora record a shift toward more cold-climate-adapted species. The two principal suggested explanations of this transition are a decline in atmospheric CO2 and changes to ocean gateways, while orbital forcing likely influenced the precise timing of the glaciation. Here we review and synthesise proxy evidence of palaeogeography, temperature, ice sheets, ocean circulation and CO2 change from the marine and terrestrial realms. Furthermore, we quantitatively compare proxy records of change to an ensemble of climate model simulations of temperature change across the EOT. The simulations compare three forcing mechanisms across the EOT: CO2 decrease, palaeogeographic changes and ice sheet growth. Our model ensemble results demonstrate the need for a global cooling mechanism beyond the imposition of an ice sheet or palaeogeographic changes. We find that CO2 forcing involving a large decrease in CO2 of ca. 40 % (∼325 ppm drop) provides the best fit to the available proxy evidence, with ice sheet and palaeogeographic changes playing a secondary role. While this large decrease is consistent with some CO2 proxy records (the extreme endmember of decrease), the positive feedback mechanisms on ice growth are so strong that a modest CO2 decrease beyond a critical threshold for ice sheet initiation is well capable of triggering rapid ice sheet growth. Thus, the amplitude of CO2 decrease signalled by our data–model comparison should be considered an upper estimate and perhaps artificially large, not least because the current generation of climate models do not include dynamic ice sheets and in some cases may be under-sensitive to CO2 forcing. The model ensemble also cannot exclude the possibility that palaeogeographic changes could have triggered a reduction in CO2.

Pressure of Urbanisation on the Fish Community Structure in Küçük Menderes River Basin (Turkey)

Urbanization is linked to changes in aquatic flora and fauna, including fishes, and it often leads to a decline in fish diversity, richness, and density. This study aims to determine the fish fauna and their abundance in Küçük Menderes River Basin, which is under the threat of urbanization. The field surveys were carried out in 50 different locations in lotic and lentic biotopes, and fish sampling was performed by using electro-shocker, seine-net, and gillnets in November 2017 and May 2018. A total of 21 taxa belonging to 14 families (Anguillidae, Acheilognathidae, Atherinidae, Blenniidae, Cobitidae, Cyprinidae, Gobiidae, Leuciscidae, Mugilidae, Nemacheilidae, Percidae, Poecilidae, Siluridae and Syngnathidae) was identified. Cyprinidae has the highest species richness with four taxa and the most commonly found fish species were Squalius kosswigi and Cyprinus carpio. In terms of abundance of species, Gambusia holbrooki was the most dominant fish species in Hırsız (the catch per unit effort = 23.28 n/min/m2) and Kuskudan (the catch per unit effort = 24.00 n/min/m2) streams. While Alburnus demiri, Barbus pergamonensis, Cobitis fahireae, Oxynoemacheilus germencicus, Petroleuciscus smyrnaeus and S. kosswigi are Anatolian endemics, Atherina boyeri, Carassius auratus, C. gibelio and Gambusia holbrooki are the invasive fish species in the basin.

Logging the Lambeth Group Upper Shelly Beds for the Thames Tideway Tunnel in London, UK: More than just “dark grey clay with shells”

Despite recent advances in the procedures for logging rotary borehole core, the Lambeth Group Upper Shelly Beds are often inadequately characterised during ground investigations for underground construction. With no recognised industry guidance, there has been a lack of clarity and detail in many logging records, other than a generic description of “dark grey clay with many shells and (local) hard bands.” Improvements in describing these deposits have been hindered by the relatively limited extent of their subcrop and rarity of surface exposure, allied to a lack of precedent intersection during underground construction excavation.Geological logging during construction of the Thames Tideway Tunnel has revealed a laterally continuous sequence of strata within the Upper Shelly Beds through central London. This ranges in lithology from strongly indurated shell ‘coquinas’, mudstones and limestones to organic-rich laminated clays, silts and fine sands. Abrupt changes in lithology and fossil fauna are displayed across sharp contacts between beds, indicative of rapid fluctuations in sea level (and so potentially of climate change) during the period of deposition.Notwithstanding their comparatively limited thickness of between 1.4 and 1.6 m within the area of investigation, the Upper Shelly Beds represent significant challenges for underground construction, most notably a reduction in the rate of excavation through the stronger layers of material. Early identification of the sequence has enabled modification and improvement to the on-site construction cycle and provided valuable assurance for the existing engineering design.This paper is intended to provide guidance for recognising the sequence of strata within the Upper Shelly Beds during future ground investigations in central London, with similar benefits for early recognition of the stronger layers during engineering design.

Dating of the Lower Pleistocene Vertebrate Site of Tsiotra Vryssi (Mygdonia Basin, Greece): Biochronology, Magnetostratigraphy, and Cosmogenic Radionuclides

Background and scope: The late Villafranchian large mammal age (~2.0–1.2 Ma) of the Early Pleistocene is a crucial interval of time for mammal/hominin migrations and faunal turnovers in western Eurasia. However, an accurate chronological framework for the Balkans and adjacent territories is still missing, preventing pan-European biogeographic correlations and schemes. In this article, we report the first detailed chronological scheme for the late Villafranchian of southeastern Europe through a comprehensive and multidisciplinary dating approach (biochronology, magnetostratigraphy, and cosmogenic radionuclides) of the recently discovered Lower Pleistocene vertebrate site Tsiotra Vryssi (TSR) in the Mygdonia Basin, Greece. Results: The minimum burial ages (1.88 ± 0.16 Ma, 2.10 ± 0.18 Ma, and 1.98 ± 0.18 Ma) provided by the method of cosmogenic radionuclides indicate that the normal magnetic polarity identified below the fossiliferous layer correlates to the Olduvai subchron (1.95–1.78 Ma; C2n). Therefore, an age younger than 1.78 Ma is indicated for the fossiliferous layer, which was deposited during reverse polarity chron C1r. These results are in agreement with the biochronological data, which further point to an upper age limit at ~1.5 Ma. Overall, an age between 1.78 and ~1.5 Ma (i.e., within the first part of the late Villafranchian) is proposed for the TSR fauna. Conclusions: Our results not only provide age constraints for the local mammal faunal succession, thus allowing for a better understanding of faunal changes within the same sedimentary basin, but also contribute to improving correlations on a broader scale, leading to more accurate biogeographic, palaeoecological, and taphonomic interpretations.

Drastic changes of the amphipod fauna in northern Germany and the displacement of Gammarus lacustris G.O. Sars, 1864 to relict habitats/status

The amphipod fauna of Central Europe has changed dramatically over the last century. This change has increased dramatically over the past 30 years. This dynamic is well documented in northeast Germany. This study places it in a landscape-ecological context. An example of a displacement is Gammarus lacustris G.O. Sars, 1864, a circumpolar species with a variety of habitats, but relegated to relic habitats. The species turns out to be a very weak competitor. Already with the immigration of Gammarus roeselii Gervais, 1835 (probably in the 1960s), it became a relic species in northeast Germany. Massive waves of introduction of Pontocaspian species of the genera Dikerogammarus, Pontogammarus and Echinogammarus a few decades later intensified this process for this and other species.

Wpływ czynników geogenicznych na kopalne fauny wioślarek (Cladocera) zbadanych w stanowiskach Jany i Klenica (Polska Zachodnia)

The article discusses the impact of the relief and geological structure of a large river valley on the quality of material in two cores of organic deposits. The location of both sites was highlighted, the relief of the physicographical mesoregion in which the research was carried out and the geomorphology of the immediate surroundings of the sites were characterised, and geological conditions were discussed in more detail. Sequences of changes in Cladocera subfossil fauna at both sites were presented and the obtained record of their transformations was interpreted. Additionally, the results of analyses of five selected physicochemi-cal parameters of the tested organic compositions were considered, and the obtained data were interpreted. It was concluded that the location of the studied cores in the valleys of large rivers had a significant impact on the quality of material analysed, which ultimately affects the certainty with which environmental changes and increasing human impact can be inferred and the reliability with which they can be reconstructed.

The Relationship between Salinity and Benthic Fauna Diversity and Abundance at Songkhla Port, Thailand

Jombodin, T.; Songkai, P.; Wichachucherd, B., and Rodcharoen, E., 2021. The relationship between salinity and benthic fauna diversity and abundance at Songkhla Port, Thailand. Journal of Coastal Research, 37(6), 1173–1180. Coconut Creek (Florida), ISSN 0749-0208. Benthic fauna plays an important role in marine ecosystems as the primary food for other aquatic animals, and this animal group helps reduce sediment nutrients by filter feeding. The aim of this study was to evaluate and explain the diversity and abundance of the benthic fauna community at the Songkhla port, where both human activities and environmental fluctuations affect this community. Benthic fauna and water samples were collected at 2-month intervals from January to November 2017. The results show that most physical parameters had wide ranges and varied by month. The benthic fauna in the Songkhla lagoon was observed in this study. The results showed a higher number of taxa compared with a previous study. Three phyla, namely, Annelida, Arthropoda, and Mollusca, had 25 taxa recorded in this study. Crustaceans were the most diverse (nine taxa) and abundant (2981 ± 313 ind/m2) group, followed by polychaetes (eight families, 2350 ± 288 ind/m2) and mollusks (eight taxa, 633 ± 200 ind/m2). Barnacles were the dominant group of crustaceans (2153 ± 758 ind/m2), whereas Serpulidae (1864 ± 647 ind/m2) and Mytilidae (447 ± 367 ind/m2) were the dominant families of polychaetes and mollusks, respectively. Cluster analysis showed that the distribution of benthic fauna and physicochemical water quality varied with similar patterns. Clustering gave two groups: for rainy season from November to January and for dry season from May to November. According to canonical correspondence analysis, salinity and transparency were the main environmental factors associated with the distribution pattern of benthic fauna in the area. In conclusion, the activities at the Songkhla port have not yet created problems for marine benthic fauna; instead, seasonal changes appear to drive changes in benthic fauna. However, future construction developments can affect the geographical area, complementing stresses from parameter changes at local scales.

Brittlestar diversity at the dawn of the Jenkyns Event (early Toarcian Oceanic Anoxic Event): new microfossils from the Dudelange drill core, Luxembourg

Abstract Ophiuroids, the slender-armed cousins of starfish, constitute an important component of modern marine benthos and have been used successfully in the exploration of (palaeo)-ecological and evolutionary trends, yet their fossil record is still poorly known. One of the major gaps in the known palaeobiodiversity of this group coincides with a global palaeoenvironmental crisis during the early Toarcian (Early Jurassic, 183 myr ago), known as the Jenkyns Event. Here we describe ophiuroid remains retrieved from a series of samples from the Dudelange (Luxembourg) drill core, which spans the lower part of the Toarcian, between the top of the Pliensbachian and the onset of the Jenkyns Event. A total of 21 species are recorded, including three new genera and 12 new species. Ophiuroid diversity and abundance fluctuate in parallel with depositional facies, with lowest values coinciding with black shales. Highest diversities, including exceptional occurrences of taxa nowadays restricted to deep-sea areas, are recorded from just below the black shales, corresponding to the onset of the Jenkyns Event. Our results show that even small (100 g) bulk sediment samples retrieved from drill cores can yield numerous identifiable ophiuroid remains, thus unlocking this group for the study of faunal change across palaeoenvironmental crises.