Pasture feeding associations of european white stork Ciconia Ciconia Ciconia with herbivorous mammals and agricultural machinery: historical and geographical aspects

На основе обширных литературных данных и авторского материала представлен детальный анализ современного географического распространения пастбищных кормовых ассоциаций европейского белого аиста Ciconia ciconia ciconia с крупными травоядными млекопитающими и сельскохозяйственной техникой. Ассоциации белого аиста с землеобрабатывающей и уборочной сельскохозяйственной техникой оцениваются как антропогенные модификации кормового поведения. Рассмотрен историко-географический аспект происхождения кормовых ассоциаций белого аиста с дикими травоядными млекопитающими и домашним скотом. Предложена гипотеза независимого африканского, ближневосточного и европейского происхождения пастбищных кормовых ассоциаций белого аиста. Based on the extensive literature review and original observations, a detailed analysis of the modern geographical distribution of pasture forage associations of the European white stork Ciconia ciconia ciconia with large herbivorous mammals and agricultural machinery is presented. Associations of the white stork with land and harvesting agricultural machinery are evaluated as anthropogenic modifications of forage behavior. The historical and geographical aspect of the origin of feedingr associations of the white stork with wild herbivorous mammals and livestock is considered. The hypothesis of independent African, Middle Eastern and European origin of pasture forage associations of the white stork is proposed.

Wildfires modify the parasite loads of invasive cane toads

The frequency and severity of wildfires are increasing due to anthropogenic modifications to habitats and to climate. Post-fire landscapes may advantage invasive species via multiple mechanisms, including changes to host–parasite interactions. We surveyed the incidence of endoparasitic lungworms ( Rhabdias pseudosphaerocephala ) in invasive cane toads ( Rhinella marina ) in near-coastal sites of eastern Australia, a year after extensive fires in this region. Both the prevalence of infection and number of worms in infected toads increased with toad body size in unburned areas. By contrast, parasite load decreased with toad body size in burned areas. By killing moisture-dependent free-living lungworm larvae, the intense fires may have liberated adult cane toads from a parasite that can substantially reduce the viability of its host. Smaller toads, which are restricted to moist environments, did not receive this benefit from fires.

Landscape of stress: Tree mortality influences physiological stress and survival in a native mesocarnivore

Climate change and anthropogenic modifications to the landscape can have both positive and negative effects on an animal. Linking landscape change to physiological stress and fitness of an animal is a fundamental tenet to be examined in applied ecology. Cortisol is a glucocorticoid hormone that can be used to indicate an animal’s physiological stress response. In the Sierra Nevada Mountains of California, fishers (Pekania pennanti) are a threatened mesocarnivore that have been subjected to rapid landscape changes due to anthropogenic modifications and tree mortality related to a 4-year drought. We measured cortisol concentrations in the hair of 64 fishers (41 females, 23 males) captured and radio-collared in the Sierra National Forest, California. We addressed two main questions: (1) Is the physiological stress response of fishers influenced by anthropogenic factors, habitat type, canopy cover, and tree mortality due to drought in their home range? (2) Does the physiological stress response influence survival, reproduction, or body condition? We examined these factors within a fisher home range at 3 scales (30, 60, 95% isopleths). Using model selection, we found that tree mortality was the principle driver influencing stress levels among individual fishers with female and male fishers having increasing cortisol levels in home ranges with increasing tree mortality. Most importantly, we also found a link between physiological stress and demography where female fishers with low cortisol levels had the highest annual survival rate (0.94), whereas females with medium and high cortisol had lower annual survival rates, 0.78 and 0.81, respectively. We found no significant relationships between cortisol levels and body condition, male survival, or litter size. We concluded that tree mortality related to a 4-year drought has created a “landscape of stress” for this small, isolated fisher population.

Anthropogenic Modifications to Estuaries Facilitate the Invasion of Non-Native Species

New observations of non-indigenous species (NIS) in coastal waters, such as the Gulf of Cadiz (Spain) have increased since 1980 and more or less exponentially in the last five years. Ballast water has become the most significant pathway for unintentional introductions of NIS into marine ecosystems. For example, the marine larvae of crustacean decapods that inhabit the water column could be transported in ballast water. Although elevated concentrations of metals are toxic to many marine organisms, some of them have evolved effective detoxification, or avoidance mechanisms making it possible to consider they have a superior ability to withstand exposures to these toxicants. In this text, we try to reinforce the hypothesis that anthropogenic modifications (such as chemical alterations and modified environments) benefit NIS with broad environmental tolerances. Taking these risks into account, a reinforcement of efficient Ballast Water Management Systems to respond to today’s challenging environmental conditions is discussed.

Assessment of the naturalness and anthropogenic transformation of the habitats of small mountain streams in different climate zones

The study compares the quality of the habitats of mountain streams in sections without visible human integration and those permanently transformed by human activity between mountain areas in different climate zones. Three mountain streams with small catchments (10–20 km2) characterized by different natural conditions were selected for the research. The selected streams are Bystrzanka (Beskid Niski, Polish Carpathians), Peshok (Darjeeling Himalaya in India), and Fanshen (Hengduan Shan in China). Field studies were carried out using the British River Habitat Survey (RHS) method. Habitat quality was analyzed based on the following indicators: Habitat Quality Assessment (HQA) and Habitat Modification Score (HMS). The obtained results indicated that sections of mountain streams located in upper catchment areas show greater habitat naturalness in relation to stream sections in lower areas. This results from the greater variety and number of natural hydromorphological elements in streams and the close vicinity of channels. In both upper and lower stream sections, regardless of the degree of naturalness and anthropopressure, the same RHS attributes have the greatest impact on the HQA and HMS values. Similar regularities in the degree of naturalness and anthropogenic modifications of the habitat between the upper and lower reaches of streams can be also expected in other mountain areas, apart from areas not affected by human activities.

The Effects of Wind-Driven Storm Events on Partly Sheltered Estuarine Beaches in Batemans Bay, New South Wales, Australia

Extreme wind-driven storm events have the potential to erode beach systems. Along the East Coast of Australia, storm events have been responsible for beach erosion in many coast-facing, open beaches. This paper investigates the potential impacts of wind-driven storms on partly sheltered estuarine beaches—a niche found within Batemans Bay, New South Wales (NSW), along the East Coast. It combines beach geomorphological data with meteorological and oceanographic data to evaluate the impacts of large storm events on three partly sheltered estuarine embayed beaches (Cullendulla Beach, Corrigans Beach, and Maloney’s Beach). The results show that while embayed beaches are protected from some storm events, storm impacts may vary with the season due to wind speed and direction changes, the presence of nearby rivers or creeks, and anthropogenic modifications such as dredging and coastline alterations. This study may contribute to the understanding of the erosive impacts of storms and help improve management strategies used to prevent recession, particularly on embayed beaches.

Effect of anthropogenic modifications on homogenization of ant community composition along elevational gradients in Cameroon

Anthropogenic modifications are recognized as one of the main factor threatening native fauna diversity and may lead to biotic homogenization. This ecological process has been described for some groups of organisms, but little is known in ants. In this study, we investigated the relationship between diversity, similarity and level of disturbance among ant communities in two mountain types (disturbed and less disturbed) from November 2017 to April 2019. Ants were sampled in four elevational levels (800 m, 900 m, 1000 m and 1,100m) using pitfall trapping and hand collection. Overall, 138 species corresponding to 2,445 occurrences were found in the two habitat types. In disturbed sites, ant species richness and occurrence were more than seven-fold higher in disturbed sites (131 species and 2,354 occurrences) than in less disturbed sites (19 and 91, respectively). Myrmicinae and Ponerinae were the most common subfamilies in disturbed and less disturbed sites respectively. The generalist ant Anoplolepis tenella was the most frequent ant species in disturbed sites whereas the specialist predator Paltothyreus tarsatus was the most common in less disturbed sites. Consistent with previous studies, this study demonstrates an increase in species richness and occurrence of generalist species with an increase in human disturbance. Likewise, our findings indicate that human disturbance is driving declines of dissimilarity among ant community thereby affecting the biological differences in ant communities. This study has implications for the management of montane forests and restriction of anthropogenic activities in these vulnerable tropical ecosystems.

The Impact of Embankments on the Geomorphic and Ecological Evolution of the Deltaic Landscape of the Indo-Bangladesh Sundarbans

The deltaic landscape of the Ganga-Brahmaputra delta has evolved through a complex interplay of geomorphic processes and tidal dynamics coupled with the anthropogenic modifications brought over in course of the reclamation of the islands since the late 18th century. The reclamation process was characterized by clearing lands for paddy farms and fish ponds by building a mesh of earthen embankments along creek banks to restrict saltwater intrusion. The length of the embankments in the Indian Sundarbans alone is 3638 km (World Bank, 2014) which altered the tidal inundation regimes, sediment accretion and geomorphic character of the deltaic inlets. The mean annual sedimentation rate (2.3 cm y−1) in the central Ganga-Brahmaputra delta is over two times higher than sedimentation within the natural intertidal setting of the Sundarbans (Rogers et al., 2017). The tidal range has also increased inland due to polder construc¬tion, with high water levels within the polder zone increasing as much as 1.7 cm y−1 (Pethick and Orford, 2013). Embankments have impacted on the biodiversity and physiological adaptations of mangroves within the sphere of tidal ingression, habitat fragmentation and seedling establishment. The chapter attempts to reappraise the impact of dykes on the geomorphology of the deltaic landscape and on the functionalities of mangrove forests.

Multi-stage Holocene evolution of the River Murray Estuary, South Australia

The River Murray Estuary, South Australia exhibits a morphology typical of a wave-dominated estuary and comprises two large, shallow central basin lakes – Lakes Alexandrina and Albert. Contested interpretations of the estuary’s limnological history and uncertainty surrounding the sustainability of current basin water usage practice warrant a robust investigation into how the system has evolved. Here we combine lithostratigraphic, geochemical and sedimentological evidence from a transect of sediment cores to reconstruct the sediment infill history of the system. We uncover multiple stages of sediment infill over the history of the system, associated with (1) the low gradient morphology of the estuary and lower river channel, (2) the mid- to late-Holocene sea-level regression and (3) anthropogenic modifications to the fluvio-estuarine system. We show that while estuarine conditions in the system were fully established during the mid-Holocene highstand (~6.4 kyr BP), central basin facies sedimentation was focussed further inland before prograding with the lowering of base level and shifting of tidal influence as sea-level fell. Central basin facies sedimentation within northern Lake Albert occurred from 5.4 to 4.0 cal kyr BP at ~0.25 cm yr-1. The uppermost accumulation of this unit was eroded by continued reduction in base level until sea-level regression concluded at 3.5 cal kyr BP. Barrage and weir installation (1940 CE) re-initiated and expanded central basin facies sedimentation in the estuary (~0.32 cm yr-1). Recently deposited sediments exhibit geochemical markers of increased trophy and more frequent acid sulfate soil acidification, exposing human impacts on the estuary.