Time of day, age and feeding habits influence coccidian oocyst shedding in wild passerines

The eastern water rat, Hydromys chrysogaster, lives in inland waters, estuaries, sea beaches and islands from Queensland to South Australia and Tasmania. It is adapted to semiaquatic life and changes in its molar teeth may be an adaptation to diet of crustaceans and molluscs. The present study was of 408 stomach contents and 316 contents of caecum with rectum, collected in New South Wales in 1970-73 from permanent Typha swamp. From elsewhere there were 12 other stomach and 11 gut contents and live rats were observed. At any time of day but particularly in evenings the rats swam along the bank or between logs or reed clumps, foraging and catching fish. Captive rats crushed small mussels and left large mussels to open by exposure. Diet varied with season and included crustaceans, mostly the yabbie, a crayfish (Cherax destructor), spiders, all Araneida with one identified as of the suborder Pisauridae, a fishing spider. Insects were the main food and were eaten in all seasons, and included larvae, nymphs and adults. Only 1% of rats had the freshwater mussel Veksurio ambiguus but the flesh was difficult to identify and empty shells were often found. Fish were eaten all the year, and were found in up to 35% of rats in autumn and winter; fish may be underestimated because flesh is not easily recognised and hard parts are not much eaten. Several species of fish, mostly introduced, were identified, their ages estimated from their scales, and length was calculated to be up to 36 cm. Frogs and macquaria tortoise (Emydura macquarii) were eaten. Birds were eaten all the year and were in up to 10% of stomachs in winter. Personal communications are quoted, from persons having seen H. chrysogaster capture large adult birds including duck and mutton bird (Puffinus tenuirostris). Captive rats were able to open cracked hen's eggs but left intact eggs. Plant material was eaten as food and possibly also in stomachs of prey. For 3 rats half the starch content was plant; 3 other stomachs had 5, 40 and 50% plant material, Azolla fuliculoides. Differences in diet with age are described. H. chrysogaster was an adaptable and opportunist feeder, making use of transient plenty of insects, exploiting plagues among other species and using plants during shortage of food. They may control introduced pests such as perch, or control yabbies in irrigation ditches.

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Statistical modelling reveals spatial, temporal, and environmental preferences for white sharks at an oceanic aggregation site

Marine Ecology Progress Series ◽

10.3354/meps13528 ◽

2020 ◽

Vol 655 ◽

pp. 171-183

Author(s):

EE Becerril-García ◽

RO Martínez-Rincón ◽

F Galván-Magaña ◽

O Santana-Morales ◽

EM Hoyos-Padilla

Keyword(s):

Feeding Habits ◽

Generalized Additive Models ◽

Statistical Modelling ◽

Time Of Day ◽

White Shark ◽

Additive Models ◽

Environmental Preferences ◽

Data Set ◽

Aggregation Site ◽

Guadalupe Island

Guadalupe Island, Mexico, is one of the most important white shark (Carcharodon carcharias) aggregation sites in the Eastern Pacific. In the waters surrounding Guadalupe Island, cage diving has been carried out since 2001 during August-November; however, there is scarce information regarding the factors associated with this seasonal aggregation. The purpose of this study was to describe the probability of occurrence of white sharks relative to spatial, temporal, and environmental factors in Guadalupe Island. Generalized additive models (GAMs) were used to describe the effect of sea surface temperature, water visibility, tide, moon phase, cloud cover, time of day, and location on white shark occurrence. GAMs were generated from a data set of 6266 sightings of white sharks, classified as immature males, mature males, immature females, and mature females. A sexual segregation related to month was observed, where females arrived after males during late September. GAMs evidenced a segregation of white sharks according to the analysed variables, which is consistent with previous observations in this locality. Environmental preferences for each white shark category are potentially influenced by feeding habits, sexual maturation, and reproduction. This study constitutes a baseline of the effect of the environment on the occurrence of white sharks in Guadalupe Island, which can be used in further studies regarding management and conservation in future climatic and anthropogenic scenarios. Its relevance is related to the understanding of its ecology in oceanic environments and the presence of this threatened species during the ecotourism season.

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DISTRIBUTION PATTERNS, BODY SIZE, AND SUGAR-FEEDING HABITS OF TWO SPECIES OF CHRYSOPS (DIPTERA: TABANIDAE)

The Canadian Entomologist ◽

10.4039/ent132213-2 ◽

2000 ◽

Vol 132 (2) ◽

pp. 213-221 ◽

Cited By ~ 4

Author(s):

A. Ossowski ◽

F.F. Hunter

Keyword(s):

Wing Length ◽

Feeding Habits ◽

Distribution Patterns ◽

Forest Edge ◽

Time Of Day ◽

Floral Nectar ◽

Carbohydrate Source ◽

Sugar Feeding ◽

Layer Chromatography ◽

Provincial Park

AbstractTwo deer fly species, Chrysops mitis Osten Sacken and Chrysops excitans Walker, were collected by sweep-netting around human bait on five collection dates in Algonquin Provincial Park, Ontario. Distribution patterns of the two species at two sites (abandoned airfield and Davies bog), in two habitats (open and forest edge), and at two times of day (morning and afternoon) are analysed. Chrysops excitans was more frequently collected than C. mitis. Regardless of site, both species are more common in the morning than the afternoon collections and both are more common in the open than the forest-edge habitats. Chrysops excitans was the larger species (based on wing length measurements) and its size was constant regardless of site, habitat, and time of day. In contrast, afternoon-collected C. mitis were larger than morning-collected flies at the Davies bog site. The crop contents of 241 flies were identified using thin-layer chromatography. Using melezitose and stachyose as honeydew-indicator sugars, the relative importance of homopteran honeydew and floral nectar as carbohydrate sources for these flies was determined. We found no significant differences among species, sites, habitats, or times of day. Overall, 52.8% of C. excitans and 51.1% of C. mitis had recently fed on homopteran-derived honeydew sugars, underscoring the importance of this carbohydrate source for the haematophagous Diptera.

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Ant-App-DB: a smart solution for monitoring arthropods activities, experimental data management and solar calculations without GPS in behavioral field studies

F1000Research ◽

10.12688/f1000research.5931.2 ◽

2015 ◽

Vol 3 ◽

pp. 311 ◽

Cited By ~ 1

Author(s):

Zeeshan Ahmed ◽

Saman Zeeshan ◽

Pauline Fleischmann ◽

Wolfgang Rössler ◽

Thomas Dandekar

Keyword(s):

Experimental Data ◽

Data Management ◽

Feeding Habits ◽

Smart Phone ◽

Field Studies ◽

Time Of Day ◽

Direct Access ◽

Ecological Data ◽

Solar Position ◽

Smart Phone Application

Field studies on arthropod ecology and behaviour require simple and robust monitoring tools, preferably with direct access to an integrated database. We have developed and here present a database tool allowing smart-phone based monitoring of arthropods. This smart phone application provides an easy solution to collect, manage and process the data in the field which has been a very difficult task for field biologists using traditional methods. To monitor our example species, the desert ant Cataglyphis fortis, we considered behavior, nest search runs, feeding habits and path segmentations including detailed information on solar position and Azimuth calculation, ant orientation and time of day. For this we established a user friendly database system integrating the Ant-App-DB with a smart phone and tablet application, combining experimental data manipulation with data management and providing solar position and timing estimations without any GPS or GIS system. Moreover, the new desktop application Dataplus allows efficient data extraction and conversion from smart phone application to personal computers, for further ecological data analysis and sharing. All features, software code and database as well as Dataplus application are made available completely free of charge and sufficiently generic to be easily adapted to other field monitoring studies on arthropods or other migratory organisms. The software applications Ant-App-DB and Dataplus described here are developed using the Android SDK, Java, XML, C# and SQLite Database.

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Applying and refining DNA analysis to determine the identity of plant material extracted from the digestive tracts of katydids

PeerJ ◽

10.7717/peerj.6808 ◽

2019 ◽

Vol 7 ◽

pp. e6808 ◽

Cited By ~ 1

Author(s):

Laurel B. Symes ◽

Nicole L. Wershoven ◽

Lars-Olaf Hoeger ◽

Jessica S. Ralston ◽

Sharon J. Martinson ◽

...

Keyword(s):

Plant Material ◽

Dna Analysis ◽

Feeding Habits ◽

Time Of Day ◽

Barro Colorado Island ◽

Gut Contents ◽

Neotropical Forest ◽

Amplification Success ◽

Significant Difference ◽

Primer Sets

Background Feeding habits are central to animal ecology, but it is often difficult to characterize the diet of organisms that are arboreal, nocturnal, rare, or highly mobile. Genetic analysis of gut contents is a promising approach for expanding our understanding of animal feeding habits. Here, we adapt a laboratory protocol for extracting and sequencing plant material from gut contents and apply it to Neotropical forest katydids (Orthoptera: Tettigoniidae) on Barro Colorado Island (BCI) in Panama. Methods Our approach uses three chloroplast primer sets that were previously developed to identify vegetation on BCI. We describe the utility and success rate of each primer set. We then test whether there is a significant difference in the amplification and sequencing success of gut contents based on the size or sex of the katydid, the time of day that it was caught, and the color of the extracted gut contents. Results We find that there is a significant difference in sequencing success as a function of gut color. When extracts were yellow, green, or colorless the likelihood of successfully amplifying DNA ranged from ~30–60%. When gut extracts were red, orange, or brown, amplification success was exceptionally low (0–8%). Amplification success was also higher for smaller katydids and tended to be more successful in katydids that were captured earlier in the night. Strength of the amplified product was indicative of the likelihood of sequencing success, with strong bands having a high likelihood of success. By anticipating which samples are most likely to succeed, we provide information useful for estimating the number of katydids that need to be collected and minimizing the costs of purifying, amplifying, and sequencing samples that are unlikely to succeed. This approach makes it possible to understand the herbivory patterns of these trophically important katydids and can be applied more broadly to understand the diet of other tropical herbivores.

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Ant-App-DB: a smart solution for monitoring arthropods activities, experimental data management and solar calculations without GPS in behavioral field studies

F1000Research ◽

10.12688/f1000research.5931.1 ◽

2014 ◽

Vol 3 ◽

pp. 311

Author(s):

Zeeshan Ahmed ◽

Saman Zeeshan ◽

Pauline Fleischmann ◽

Wolfgang Rössler ◽

Thomas Dandekar

Keyword(s):

Experimental Data ◽

Data Management ◽

Feeding Habits ◽

Smart Phone ◽

Field Studies ◽

Time Of Day ◽

Direct Access ◽

Ecological Data ◽

Solar Position ◽

Smart Phone Application

Field studies on arthropod ecology and behaviour require simple and robust monitoring tools, preferably with direct access to an integrated database. We have developed and here present a database tool allowing smart-phone based monitoring of arthropods. This smart phone application provides an easy solution to collect, manage and process the data in the field which has been a very difficult task for field biologists using traditional methods. To monitor our example species, the desert ant Cataglyphis fortis, we considered behavior, nest search runs, feeding habits and path segmentations including detailed information on solar position and Azimuth calculation, ant orientation and time of day. For this we established a user friendly database system integrating the Ant-App-DB with a smart phone and tablet application, combining experimental data manipulation with data management and providing solar position and timing estimations without any GPS or GIS system. Moreover, the new desktop application Dataplus allows efficient data extraction and conversion from smart phone application to personal computers, for further ecological data analysis and sharing. All features, software code and database as well as Dataplus application are made available completely free of charge and sufficiently generic to be easily adapted to other field monitoring studies on arthropods or other migratory organisms. The software applications Ant-App-DB and Dataplus described here are developed using the Android SDK, Java, XML, C# and SQLite Database

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