Drone assessment of habitat selection and breeding success of Gull-billed Tern <em>Gelochelidon nilotica</em> nesting on low-accessibility sites: a case study

The use of drones in the study of waterbird breeding biology has received considerable attention in the last years, but very few studies were made along the Mediterranean. We studied habitat selection and breeding success of the Gull-billed Tern Gelochelidon nilotica in two colonies inside fish farms along the Italian Adriatic coastline, using a small, commercial drone. Both colonies were located on small islets surrounded by very shallow water and clayey bottoms, thus being difficult to access. Compared with availability, the Gull-billed Terns selected quadrats higher above the water level, with a higher vegetation cover, which lay farther from the water edge, contain less water, and which are more frequently located in the center of the islands. 147 of 178 clutches (mean clutch size ± SD: 2.61 ± 0.58) hatched 383 chicks (82.5%; 2.15 ± 1.09 chicks per nest), with large differences between the two colonies. Hatching success was 95.0% and 69.1%; the most common cause of egg loss was flooding (97.0%). Nest attendance could easily be ascertained by 30-m above ground level drone-derived imagery. The use of a drone allowed the study of some aspects of the breeding biology of the Gull Billed Tern in two breeding sites where the traditional field approach, i.e. researchers reaching the sites by boat, would have been very difficult, causing unavoidable and prolonged disturbance to the nesting adults.

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Breeding biology of common kingfisher (Alcedo atthis, Linnaeus 1758)

Journal of the Asiatic Society of Bangladesh Science ◽

10.3329/jasbs.v47i1.54184 ◽

2021 ◽

Vol 47 (1) ◽

pp. 23-34

Author(s):

Habibon Naher ◽

Noor Jahan Sarker ◽

Shawkat Imam Khan

Keyword(s):

Natural Disaster ◽

Breeding Season ◽

Body Length ◽

Breeding Success ◽

Hatching Success ◽

Total Body Length ◽

Breeding Biology ◽

The Common ◽

Total Body

The breeding biology of the common kingfisher (Alcedo atthis) was studied from 2008 to 2011 in Dhaka North City Corporation and Savar Upazilla. The breeding season was April to September. It laid 3 to 7 glossy white, almost round eggs with a size of 2.5±0.3 cm length, 2.2±0.3 cm breadth, and 5.3±0.7g weight. It incubated for 16 to 21 days. During hatching, the hatchlings’ weight ranged from 8.5 to 10.5 g and total body length from 43.2 to 58.6 mm whereas, it was 30.1 to 32.7 g and 151 to 155.5 mm, respectively, during fledging. Hatching success was 83.3%. Stolen by people (13.9%) and infertility (2.8%) were the causes of egg loss. The young birds fledged out after 21 to 27 days of hatching. A total of 56.7% of nestlings were unable to fly due to stolen (43.3%), deaths due to unknown reasons (6.7%) and deaths due to natural disaster (6.7%). The breeding success was 36.1% in relation to eggs laid and 43.3% in relation to eggs hatched. J. Asiat. Soc. Bangladesh, Sci. 47(1): 23-34, June 2021

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Breeding biology of American crows in Saskatchewan parkland habitat

Canadian Journal of Zoology ◽

10.1139/z91-026 ◽

1991 ◽

Vol 69 (1) ◽

pp. 168-175 ◽

Cited By ~ 4

Author(s):

Jordan B. Ignatiuk ◽

Robert G. Clark

Keyword(s):

Hatching Success ◽

Egg Laying ◽

Breeding Biology ◽

Breeding Habitat ◽

Breeding Sites ◽

Corvus Brachyrhynchos ◽

Aspen Parkland ◽

American Crows ◽

Clutch Initiation ◽

Bill Length

The breeding biology of American crows (Corvus brachyrhynchos) was studied in two areas (St. Denis and Elstow) of aspen parkland habitat in Saskatchewan, Canada, in 1987 and 1988. The St. Denis area had relatively more diverse land use and contained more wetlands than the Elstow area. Crows returned from winter ranges in early April and were frequently observed at breeding sites in late April, when nest building began. Overall, mean (± SD) clutch initiation dates were 6 May (± 6 days) at St. Denis and 10 May (± 6) at Elstow, but, in 1988, clutches were initiated about 6 days earlier at St. Denis than at Elstow (P < 0.05). Density of nests at St. Denis averaged twice that found at Elstow (0.70 and 0.35/km2, respectively; P < 0.05). Size of incubated clutches did not differ between years or areas, and averaged 4.8 ± 0.6 eggs (n = 104). Hatching success did not differ by year or area, but in 1987, nests at St. Denis produced nearly twice as many young as at Elstow. Brood losses resulted from predation, starvation, and possibly other factors. Chicks in smaller broods gained mass faster and fledged at a lighter mass than chicks in larger broods. There were no consistent differences between areas in the mass, bill length, and head–bill lengths of 22-day-old chicks. Young fledged when they were between 30 and 34 days old. Crows at St. Denis had higher reproductive success (1987), nested at greater densities (1988 and both years combined), and began egg laying earlier (1988) than at Elstow, suggesting that St. Denis was a more productive breeding habitat.

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Shift in the Community Attitude- Case Study on Swatchta Abhiyan Ground Level Impact

SSRN Electronic Journal ◽

10.2139/ssrn.3638899 ◽

2020 ◽

Author(s):

Ashish Sharma ◽

Ashish Yadav

Keyword(s):

Ground Level ◽

Community Attitude

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Development of a chimeric odour blend for attracting gravid malaria vectors

Malaria Journal ◽

10.1186/s12936-021-03797-w ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Betelehem Wondwosen ◽

Mengistu Dawit ◽

Yared Debebe ◽

Habte Tekie ◽

Sharon R. Hill ◽

...

Keyword(s):

Vector Control ◽

Binary Logistic Regression ◽

Ground Level ◽

Malaria Vectors ◽

Volatile Components ◽

Innovative Strategy ◽

Breeding Sites ◽

Logistic Regression Models ◽

Plant Feeding ◽

Global Vector

Abstract Background Odour-based tools targeting gravid malaria vectors may complement existing intervention strategies. Anopheles arabiensis are attracted to, and stimulated to oviposit by, natural and synthetic odours of wild and domesticated grasses associated with mosquito breeding sites. While such synthetic odour lures may be used for vector control, these may have limited efficacy when placed in direct competition with the natural source. In this study, workflows developed for plant-feeding pests was used to design and evaluate a chimeric odour blend based on shared attractive compounds found in domesticated grass odours. Methods Variants of a synthetic odour blend, composed of shared bioactive compounds previously identified in domesticated grasses, was evaluated sequentially in a two-choice olfactometer to identify a ratio-optimized attractive blend for malaria vectors. During this process, blends with ratios that were significantly more attractive than the previously identified synthetic rice blend were compared to determine which was most attractive in the two-choice olfactometer. To determine whether all volatile components of the most attractive blend were necessary for maximal attraction, subtractive assays were then conducted, in which individual components were removed for the most attractive blend, to define the final composition of the chimeric blend. Binary logistic regression models were used to determine significance in all two-choice assays. The chimeric blend was then assessed under field conditions in malaria endemic villages in Ethiopia, to assess the effect of dose, trap type, and placement relative to ground level. Field data were analyzed both descriptively and using a Welch-corrected t-test. Results A ratio-optimized chimeric blend was identified that significantly attracted gravid An. arabiensis under laboratory conditions. In the field, trap captures of An. arabiensis and Anopheles pharoensis were dependent on the presence of the lure, trap type (CDC, BG Sentinel and Suna traps), placement relevant to ground level, with low release rates generally luring more mosquitoes. Conclusions The workflow designed for the development of chimeric lures provides an innovative strategy to target odour-mediated behaviours. The chimeric lure identified here can be used in existing trapping systems, and be customized to increase sustainability, in line with goals of the Global Vector Control Response Group.

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Threat to food security under current levels of ground level ozone: A case study for Indian cultivars of rice

Atmospheric Environment ◽

10.1016/j.atmosenv.2010.06.022 ◽

2010 ◽

Vol 44 (34) ◽

pp. 4272-4282 ◽

Cited By ~ 41

Author(s):

Richa Rai ◽

Madhoolika Agrawal ◽

S.B. Agrawal

Keyword(s):

Food Security ◽

Ground Level ◽

Ground Level Ozone

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Synergetic monitoring of Saharan dust plumes and potential impact on surface: a case study of dust transport from Canary Islands to Iberian Peninsula

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-3067-2011 ◽

2011 ◽

Vol 11 (7) ◽

pp. 3067-3091 ◽

Cited By ~ 63

Author(s):

C. Córdoba-Jabonero ◽

M. Sorribas ◽

J. L. Guerrero-Rascado ◽

J. A. Adame ◽

Y. Hernández ◽

...

Keyword(s):

Iberian Peninsula ◽

Particle Deposition ◽

Ground Level ◽

In Situ Measurements ◽

Saharan Dust ◽

Dust Transport ◽

Air Masses ◽

Potential Impact

Abstract. The synergetic use of meteorological information, remote sensing both ground-based active (lidar) and passive (sun-photometry) techniques together with backtrajectory analysis and in-situ measurements is devoted to the characterization of dust intrusions. A case study of air masses advected from the Saharan region to the Canary Islands and the Iberian Peninsula, located relatively close and far away from the dust sources, respectively, was considered for this purpose. The observations were performed over three Spanish geographically strategic stations within the dust-influenced area along a common dust plume pathway monitored from 11 to 19 of March 2008. A 4-day long dust event (13–16 March) over the Santa Cruz de Tenerife Observatory (SCO), and a linked short 1-day dust episode (14 March) in the Southern Iberian Peninsula over the Atmospheric Sounding Station "El Arenosillo" (ARN) and the Granada station (GRA) were detected. Meteorological conditions favoured the dust plume transport over the area under study. Backtrajectory analysis clearly revealed the Saharan region as the source of the dust intrusion. Under the Saharan air masses influence, AERONET Aerosol Optical Depth at 500 nm (AOD500) ranged from 0.3 to 0.6 and Ångström Exponent at 440/675 nm wavelength pair (AE440/675) was lower than 0.5, indicating a high loading and predominance of coarse particles during those dusty events. Lidar observations characterized their vertical layering structure, identifying different aerosol contributions depending on altitude. In particular, the 3-km height dust layer transported from the Saharan region and observed over SCO site was later on detected at ARN and GRA stations. No significant differences were found in the lidar (extinction-to-backscatter) ratio (LR) estimation for that dust plume over all stations when a suitable aerosol scenario for lidar data retrieval is selected. Lidar-retrieved LR values of 60–70 sr were obtained during the main dust episodes. These similar LR values found in all the stations suggest that dust properties were kept nearly unchanged in the course of its medium-range transport. In addition, the potential impact on surface of that Saharan dust intrusion over the Iberian Peninsula was evaluated by means of ground-level in-situ measurements for particle deposition assessment together with backtrajectory analysis. However, no connection between those dust plumes and the particle sedimentation registered at ground level is found. Differences on particle deposition processes observed in both Southern Iberian Peninsula sites are due to the particular dust transport pattern occurred over each station. Discrepancies between columnar-integrated and ground-level in-situ measurements show a clear dependence on height of the dust particle size distribution. Then, further vertical size-resolved observations are needed for evaluation of the impact on surface of the Saharan dust arrival to the Iberian Peninsula.

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