Road mortality of the eastern long-necked turtle (Chelodina longicollis) along the Murray River, Australia: an assessment using citizen science

2018 ◽  
Vol 66 (1) ◽  
pp. 41 ◽  
Author(s):  
Claudia Santori ◽  
Ricky-John Spencer ◽  
James U. Van Dyke ◽  
Michael B. Thompson
Keyword(s):  
Citizen Science ◽  
Management Practices ◽  
Habitat Destruction ◽  
Road Mortality ◽  
Freshwater Turtles ◽  
Introduced Predators ◽  
Murray River ◽  
Time Of Year ◽  
Rain Events ◽  
Chelodina Longicollis

Turtles face a variety of threats (e.g. habitat destruction, introduced predators) that are pushing many species towards extinction. Vehicle collisions are one of the main causes of mortality of adult freshwater turtles. To conceptualise the level of threat that roads pose to Australians turtles, we analysed data gathered through the citizen science project TurtleSAT along the Murray River. We recorded 124 occurrences of turtle road mortality, which included all three local species (Chelodina expansa, Chelodina longicollis, and Emydura macquarii). Chelodina longicollis was the most commonly reported species killed on roads. We found that rain and time of year affect the likelihood of C. longicollis being killed on roads: increased turtle mortality is associated with rain events and is highest during the month of November, which coincides with their nesting season. Chelodina longicollis was most likely to be killed on the Hume Highway and roads around major urban centres; therefore, we recommend that governing bodies focus management practices and increase awareness at these locations. The degree of road mortality that we detected in this study requires mitigation, as it may contribute to the decline of C. longicollis along the Murray River.

Food abundance and diet variation in freshwater turtles from the mid-Murray River, Australia

2018 ◽  
Vol 66 (1) ◽  
pp. 67 ◽  
Author(s):  
Kristen Petrov ◽  
Jessica Lewis ◽  
Natasha Malkiewicz ◽  
James U. Van Dyke ◽  
Ricky-John Spencer
Keyword(s):  
Green Algae ◽  
Prey Availability ◽  
Foraging Strategies ◽  
Freshwater Turtles ◽  
Food Items ◽  
Filamentous Green Algae ◽  
Invertebrate Diversity ◽  
Murray River ◽  
Specialist Species ◽  
Chelodina Longicollis

Consumers usually respond to variations in prey availability by altering their foraging strategies. Generalist consumers forage on a diversity of resources and have greater potential to ‘switch’ their diet in response to fluctuations in prey availability, in comparison to specialist consumers. We aimed to determine how the diets of two specialist species (the eastern long-necked turtle (Chelodina longicollis) and the broad-shelled turtle (Chelodina expansa) and the more generalist Murray River short-necked turtle (Emydura macquarii) respond to variation in habitat and prey availability. We trapped and stomach-flushed turtles, and compared their diets along with environmental variables (turbidity, macrophyte and filamentous green algae cover, and aquatic invertebrate diversity and abundance) at four wetlands in north-central Victoria. Diets of E. macquarii differed from those of both Chelodina species, which overlapped, across all four sites. However, samples sizes for the two Chelodina species were too small to compare among-wetland variation in diet. Dietary composition of E. macquarii was variable but did not differ statistically among sites. Emydura macquarii preferentially selected filamentous green algae at three of the four sites. Where filamentous green algae were rare, total food bolus volume was reduced and E. macquarii only partially replaced it with other food items, including other vegetation, wood, and animal prey. Many turtles at these sites also had empty stomachs. Thus, filamentous green algae may be a limiting food for E. macquarii. Although E. macquarii has previously been described as a generalist, it appears to have limited ability to replace filamentous green algae with other food items when filamentous green algae are rare.

Ecological and physiological impacts of salinisation on freshwater turtles of the lower Murray River

2012 ◽  
Vol 39 (8) ◽  
pp. 705 ◽  
Author(s):  
Deborah S. Bower ◽  
Clare E. Death ◽  
Arthur Georges
Keyword(s):  
Saline Lake ◽  
South Australia ◽  
Freshwater Turtle ◽  
Plasma Sodium ◽  
Freshwater Species ◽  
Freshwater Turtles ◽  
Brackish Lake ◽  
Ecological Processes ◽  
Murray River ◽  
Chelodina Longicollis

Context The increasing intensity and extent of anthropogenically mediated salinisation in freshwater systems has the potential to affect freshwater species through physiological and ecological processes. Determining responses to salinisation is critical to predicting impacts on fauna. Aims We aimed to quantify the response of wild-caught turtles from freshwater lakes that had become saline in the lower Murray River catchment. Methods Plasma electrolytes of all three species of freshwater turtle from South Australia were compared among two freshwater sites (Horseshoe Lagoon and Swan Reach), a brackish lake (Lake Bonney) and a saline lake (Lake Alexandrina). Key results Chelodina longicollis, C. expansa and Emydura macquarii from a brackish lake had higher concentrations of plasma sodium and chloride than those from freshwater habitats. However, osmolytes known to increase under severe osmotic stress (urea and uric acid) were not elevated in brackish sites. Turtles from the highly saline lake were colonised by an invasive marine worm which encased the carapace and inhibited limb movement. Conclusions Freshwater turtles in brackish backwaters had little response to salinity, whereas the C. longicollis in a saline lake had a significant physiological response caused by salt and further impacts from colonisation of marine worms. Implications Short periods of high salinity are unlikely to adversely affect freshwater turtles. However, secondary ecological processes, such as immobilisation from a marine worm may cause unexpected impacts on freshwater fauna.

Declines of freshwater turtles associated with climatic drying in Australia

2011 ◽  
Vol 38 (8) ◽  
pp. 664 ◽  
Author(s):  
Bruce C. Chessman
Keyword(s):  
River Flow ◽  
Freshwater Turtle ◽  
Severe Drought ◽  
Freshwater Turtles ◽  
Catch Per Unit Effort ◽  
Unit Effort ◽  
Murray River ◽  
Floodplain Inundation ◽  
Global Impacts ◽  
Chelodina Longicollis

Context While much attention has been paid to the effects of global temperature increases on the geographical ranges and phenologies of plants and animals, less is known about the impacts of climatically driven alteration of water regimes. Aims To assess how three species of freshwater turtle in Australia’s Murray–Darling Basin have responded to long-term decline in river flow and floodplain inundation due to climatic drying and water diversions. Methods Turtle populations were sampled in a section of the Murray River and its floodplain in 1976–82 following a wet period and in 2009–11 at the end of the most severe drought on record. Catch per unit effort, proportional abundance in different habitat types and population structure were assessed in both periods. Key results Catch per unit effort in baited hoop nets declined by 91% for the eastern snake-necked turtle (Chelodina longicollis) and 69% for the Murray turtle (Emydura macquarii), but did not change significantly for the broad-shelled turtle (Chelodina expansa). In addition, total catches from a range of sampling methods revealed a significantly reduced proportion of juvenile C. longicollis and E. macquarii in 2009–11, suggesting a fall in recruitment. Key conclusions The decline of C. longicollis was likely due mainly to drought-induced loss of critical floodplain habitat in the form of temporary water bodies, and that of E. macquarii to combined effects of drought and predation on recruitment. C. expansa seems to have fared better than the other two species because it is less vulnerable to nest predation than E. macquarii and better able than C. longicollis to find adequate nutrition in the permanent waters that remain during extended drought. Implications Declining water availability may be a widespread threat to freshwater turtles given predicted global impacts of climate change and water withdrawals on river flows. Understanding how each species uses particular habitats and how climatic and non-climatic threats interact would facilitate identification of vulnerable populations and planning of conservation actions.

Monitoring Effects of Catchment Management Practices on Phosphorus Loads into the Eutrophic Peel-Harvey Estuary, Western Australia

1986 ◽  
Vol 18 (4-5) ◽  
pp. 53-61 ◽  
Author(s):  
P. B. Birch ◽  
G. G. Forbes ◽  
N. J. Schofield
Keyword(s):  
Management Practices ◽  
Major Change ◽  
High Flow ◽  
Catchment Management ◽  
Flow Rates ◽  
Early Results ◽  
Phosphorus Loads ◽  
Time Of Year ◽  
High Runoff

Early results from monitoring runoff suggest that the programme to reduce application of superphosphate to farmlands in surrounding catchments has been successful in reducing input of phosphorus to the eutrophic Peel-Harvey estuary. In the estuary this phosphorus fertilizes algae which grow in abundance and accumulate and pollute once clean beaches. The success of the programme has been judged from application of an empirical statistical model, which was derived from 6 years of data from the Harvey Estuary catchment prior to a major change in fertilizer practices in 1984. The model relates concentration of phosphorus with rate of flow and time of year. High phosphorus concentrations were associated with high flow rates and with flows early in the high runoff season (May-July). The model predicted that the distribution of flows in 1984 should have resulted in a flow-weighted concentration of phosphorus near the long-term average; the observed concentration was 25% below the long-term average. This means that the amount of phosphorus discharged into the Harvey Estuary could have been about 2 5% less than expected from the volume of runoff which occurred. However several more years of data are required to confirm this trend.

scholarly journals Embedding Computer Vision in Citizen Science

2019 ◽  
Vol 3 ◽  
Author(s):  
Tom August ◽  
J Terry ◽  
David Roy
Keyword(s):  
Decision Making ◽  
Computer Vision ◽  
Data Quality ◽  
Citizen Science ◽  
Learning Process ◽  
Contextual Information ◽  
Limited Resource ◽  
Machine Learning Techniques ◽  
Ecological Knowledge ◽  
Time Of Year

The rapid rise of Artificial Intelligence (AI) methods has presented new opportunities for those who work with biodiversity data. Computer vision, in particular where computers can be trained to identify species in digital photographs, has significant potential to address a number of existing challenges in citizen science. The Biological Records Centre (www.brc.ac.uk) has been a central focus for terrestrial and freshwater citizen science in the United Kingdom for over 50 years. We will present our research on how computer vision can be embedded in citizen science, addressing three important questions. How can contextual information, such as time of year, be included in computer vision? A naturalist will use a wealth of ecological knowledge about species in combination with information about where and when the image was taken to augment their decision making; we should emulate this in our AI. How can citizen scientists be best supported by computer vision? Our ambition is not to replace identification skills with AI but to use AI to support the learning process. How can computer vision support our limited resource of expert verifiers as data volumes increase? We receive more and more data each year, which puts a greater demand on our expert verifiers, who review all records to ensure data quality. We have been exploring how computer vision can lighten this workload. How can contextual information, such as time of year, be included in computer vision? A naturalist will use a wealth of ecological knowledge about species in combination with information about where and when the image was taken to augment their decision making; we should emulate this in our AI. How can citizen scientists be best supported by computer vision? Our ambition is not to replace identification skills with AI but to use AI to support the learning process. How can computer vision support our limited resource of expert verifiers as data volumes increase? We receive more and more data each year, which puts a greater demand on our expert verifiers, who review all records to ensure data quality. We have been exploring how computer vision can lighten this workload. We will present work that addresses these questions including: developing machine learning techniques that incorporate ecological information as well as images to arrive at a species classification; co-designing an identification tool to help farmers identify flowers beneficial to wildlife; and assessing the optimal combination of computer vision and expert verification to improve our verification systems.

scholarly journals Water Table Depth Effect on Water Use and Tuber Yield for Subirrigated Caladium Production

2002 ◽  
Vol 12 (4) ◽  
pp. 679-681 ◽  
Author(s):  
C.D. Stanley ◽  
B.K. Harbaugh
Keyword(s):  
Water Use ◽  
Water Table ◽  
Management Practices ◽  
Organic Soil ◽  
Water Table Depth ◽  
Depth Effect ◽  
Production Index ◽  
Tuber Production ◽  
Current Water ◽  
Rain Events

A study was conducted to determine the effect of water table depth on water use and tuber yields for subirrigated caladium (Caladium × hortulanum) production. A field-situated drainage lysimeter system was used to control water table depths at 30, 45 and 60 cm (11.8, 17.7, and 23.6 inches). Water use was estimated by accounting for water added or removed (after rain events) to maintain the desired water table depth treatments. In 1998, tuber weights, the number of Jumbo grade tubers, and the production index (tuber value index) of `White Christmas' were greater when plants were grown with the water table maintained at 30 or 45 cm compared to 60 cm. In 1999, tuber weights, the number of Mammoth grade tubers, and the production index, also were greater when plants were grown at water table depths of 30 or 45 cm compared to 60 cm. The average estimated daily water use was 6.6, 5.1, and 3.3 mm (0.26, 0.20, and 0.13 inch) for plants grown at water table depths of 30, 45, and 60 cm, respectively, indicating an inverse relationship with water table depth. While current water management practices in the caladium industry attempt to maintain a 60-cm water table, results from this study indicate that, for subirrigated caladium tuber production, the water table should be maintained in at 30 to 45 cm for maximum production on an organic soil.

scholarly journals Impacts of Windfarm Development Activities on Rocky Plateaus - Discussions on Chalkewadi plateau, Dist. Satara, Maharashtra

2015 ◽  
Vol 28 (1) ◽  
Author(s):  
Manasi Karandikar ◽  
Ketaki Ghate ◽  
Ketaki Kulkarni
Keyword(s):  
Land Use ◽  
Wind Farm ◽  
Management Practices ◽  
Land Use Changes ◽  
Wind Farms ◽  
Ground Level ◽  
Google Earth ◽  
Habitat Destruction ◽  
Major Activity ◽  
Reserve Forest

Rocky plateaus are ecologically very important as they harbor special diversity and are part of catchments of major rivers of Maharashtra. Detailed studies on the components and fragility of rocky plateau ecosystems are sparse. Recently, the instances of these plateaus being subjected to various land use changes without detailed assessments, have affected the balance of the complex ecosystem and the services offered by them. Windfarm development is one major activity on the rocky plateaus for which little data is available on ecosystem level impacts. Results of the present study describe the Chalkewadi plateau complex, Satara district and impacts on the plateau surface brought about by the development of a high-density windfarm. Broad observations were made on the changing land use, microhabitats and associated vegetation. Manual analysis of Google Earth images of the plateau was done to understand the nature and scale of the ground-level disturbance. Results show that even though the actual area under windmill establishment is relatively smaller compared to the total plateau area, its environmental footprint is relatively large. The network of temporary and permanent roads, created to erect and operate the windfarm, has dissected the habitat and corridors of wildlife movement. An increase in road kill incidences was observed. Roads have also initiated erosional features all along the plateau surface. Disturbance due to windfarms is widespread on the plateau with the only exception being in the Reserve Forest area and disconnected smaller plateaus. Our results complement conclusions from other studies regarding negative impacts of windfarms on birds and reptiles. Thus overall impact of windfarms, in terms of habitat destruction is significant and should be studied in depth before establishment of wind farms. Establishment of windfarms on ecologically sensitive areas should be avoided as far as possible. However, we recommend good ecological management practices that could reduce the impacts, if wind farm establishment is inevitable. The recommendations can be applied to other plateaus in Sahyadri where windfarms are already in place

scholarly journals Floristic and structural variation of weeds in eucalyptus plantations as influenced by relief and time of year

2013 ◽  
Vol 31 (3) ◽  
pp. 491-499 ◽  
Author(s):  
L.D. Tuffi Santos ◽  
O. Cardoso Filho ◽  
A. Santos Júnior ◽  
B.F. Sant'Anna-Santos ◽  
R.C. Felix ◽  
...  
Keyword(s):  
Global Positioning System ◽  
Structural Variation ◽  
Management Practices ◽  
Abundant Species ◽  
Commelina Benghalensis ◽  
Global Positioning ◽  
Eucalyptus Plantations ◽  
Time Of Year ◽  
Floristic Variation ◽  
Sida Rhombifolia

The objective of this work was to analyze the floristic variation and phytosociological structure of weeds as influenced by relief and time of year in eucalyptus plantations in Santana do Paraíso and Guanhães - MG. The total area sampled for each locality was approximately 10 ± 3 hectares, comprising three types of relief: lowland, slope, and upper area. In each type of relief, 10 plots of 1 m² were sampled, corresponding to 30 plots per locality, where they were randomly allocated in a zigzag. The taxonomic identification was performed in four assessments, corresponding to the months of November and March, comprising two ratings each season, always at the same points, and geo-referenced using the Global Positioning System (GPS). A total of 3,893 individuals, 18 families and 61 species, were identified in Santana do Paraiso and a total of 1,166 individuals, 13 families and 58 species, in Guanhães. In both localities, the most representative families in terms of wealth were: Poaceae, Asteraceae, and Fabaceae. Galinsoga parviflora was the most abundant species. The Vernonia polyantes was identified only in the lowlands, while Arrabida florida was identified in the slope and upper area. On the other hand, Emilia coccinea, Sida rhombifolia, S. paniculatum and Spermacoce latifolia were common to all three environments. Commelina benghalensis was present only in the month of March, while G. parviflora was present only in the month of November. It was concluded that the floristic and phytosociological variation of weeds in eucalyptus plantations is influenced by the type of relief and time of year, which should guide the management practices used in the culture.

scholarly journals When It Rains, It Pours: Integrating Citizen Science Methods to Understand Resilience of Urban Green Spaces

2021 ◽  
Vol 3 ◽  
Author(s):  
Bethany Pudifoot ◽  
Macarena L. Cárdenas ◽  
Wouter Buytaert ◽  
Jonathan D. Paul ◽  
Claire L. Narraway ◽  
...  
Keyword(s):  
Citizen Science ◽  
Management Practices ◽  
Green Space ◽  
Infiltration Rate ◽  
Soil Characteristics ◽  
Environmental Benefits ◽  
Green Spaces ◽  
Flow Diagram ◽  
Urban Green ◽  
Urban Green Spaces

Urban green spaces are often promoted as nature-based solutions, thus helping to mitigate the negative effects of climate change. Estimating the potential environmental benefits provided by urban green space is difficult because of inconsistencies in management practices and their heterogeneous nature. Collecting data across such a spectrum of contexts at a large scale is costly and time consuming. In this study, we explore a novel integrated method for citizen scientists to assess the flood mitigation potential of urban green spaces. In three European cities, citizen scientists measured infiltration rate and associated soil characteristics in managed and unmanaged urban green spaces. The results show that simple citizen science-based measurements can indicate the infiltration potential (i.e., high vs. low) of soil at these sites. Infiltration rate was best predicted by measurements of soil compaction, soil color, air temperature, and level of insolation (i.e., high vs. low). These simple, fast methods can be repeated over time and space by citizen scientists to provide robust estimates of soil characteristics and the infiltration potential of soils that exist in similar temperate urban areas. A classification flow diagram was constructed and validated that allows citizen scientists to carry out such tests over a wider geographical region and at a higher frequency than would be available to research scientists alone. Most importantly, it allows citizens to take actions to improve infiltration in their local green space and support local flood resilience.

Autumn de-worming

UK-Vet Equine ◽  
2021 ◽  
Vol 5 (6) ◽  
pp. 238-240
Author(s):  
David Rendle
Keyword(s):  
Management Practices ◽  
Low Risk ◽  
Clinical Disease ◽  
Parasitic Disease ◽  
Grazing Season ◽  
Time Of Year ◽  
The Individual

Autumn is traditionally a time when most horses are de-wormed with one or more products that are effective against tapeworms and both adult and larval roundworms. However, the increasing prevalence of resistance and availability of diagnostics should prompt scrutiny of whether blanket de-worming at this time of year is appropriate. If management is good and horses are at low-risk of clinical disease, then there may be no need to use anthelmintics. Serology provides a means of assessing exposure to both cyathostomins and tapeworms, but it has its limitations and does not provide a validated means of assessing the risk of parasitic disease. The results of serology, results of faecal worm egg counts performed in the population through the preceding grazing season, and knowledge of management practices in the population should all be considered when assessing whether the risk of the disease to the individual is such that it must take priority over the ever-increasing threat of resistance in the equine population.

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