scholarly journals Monitoring migratory birds in stopover habitat: assessing the value of extended duration audio recording

2020 ◽  
Author(s):  
Ellie Roark ◽  
Willson Gaul
Keyword(s):  
Species Identification ◽  
Relative Abundance ◽  
Migratory Birds ◽  
Survey Method ◽  
List Type ◽  
Point Counts ◽  
Migration Timing ◽  
Number Of Species ◽  
Extended Duration ◽  
Stopover Habitat

ABSTRACTBecause birds are frequently detected by sound, autonomous audio recorders (called automated recording units or ARUs) are now an established tool in addition to in-person observations for monitoring the status and trends of bird populations. ARUs have been evaluated and applied during breeding seasons, and to monitor the nocturnal flight calls of migrating birds. However, birds behave differently during migration stopover than during the breeding season. Here we present a method for using ARUs to monitor land birds in migration stopover habitat.We conducted in-person point counts next to continuously recording ARUs, and compared estimates of the number of species detected and focal species relative abundance from point counts and ARUs. We used a desk-based audio bird survey method for processing audio recordings, which does not require automated species identification algorithms. We tested two methods of using extended duration ARU recording: surveying consecutive minutes, and surveying randomly selected minutes.Desk-based surveys using randomly selected minutes from extended duration ARU recordings performed similarly to point counts, and better than desk-based surveys using consecutive minutes from ARU recordings. Surveying randomly selected minutes from ARUs provided estimates of relative abundance that were strongly correlated with estimates from point counts, and successfully showed the increase in abundance associated with migration timing. Randomly selected minutes also provided estimates of the number of species present that were comparable to estimates from point counts.ARUs are an effective way to track migration timing and intensity in remote or seasonally inaccessible migration stopover habitats. We recommend that desk-based surveys use randomly sampled minutes from extended duration ARU recordings, rather than using consecutive minutes from recordings. Our methods can be immediately applied by researchers with the skills to conduct point counts, with no additional expertise necessary in automated species identification algorithms.

scholarly journals A floristic survey of Fair Isle

2017 ◽  
Author(s):  
Camila V. Quinteros Peñafiel ◽  
Nick J. Riddiford ◽  
Alex D. Twyford
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Great Britain ◽  
Migratory Birds ◽  
Phase 1 ◽  
Survey Method ◽  
Botanical Survey ◽  
Floristic Survey ◽  
Number Of Species ◽  
Floristic Study

Fair Isle is a small isolated island located off the northern tip of Great Britain. Recognised internationally for rare migratory birds and important seabird colonies, the flora of Fair Isle has received far less attention. To rectify this, we present the first comprehensive floristic study of the island. A botanical survey was performed for each monad, and habitat information was collated following the NCC Phase 1 habitat survey method. These data were compiled to give a comprehensive checklist of 317 species, classified into 31 orders, 68 families and 191 genera according to APG IV. Of the total number of species, 254 are native to Great Britain and the remaining 63 are aliens. The list includes 10 species under threat, 7 nationally scarce and 1 nationally rare species. Our results reveal that even though Fair Isle is 200 times smaller than the full archipelago of Shetland, it holds a surprising one-third the number of species. The island is also notable for its complex mosaic of habitats, which include a range of communities that are rare or under threat elsewhere in the British Isles. We also provide recommendations for future monitoring to record changes in land-use and the effects of climate change.

scholarly journals Status and Diversity of Birds of Ramna Park, Dhaka, Bangladesh

2016 ◽  
Vol 43 (2) ◽  
pp. 291-301
Author(s):  
Sultana Rajia ◽  
Md Mahabub Alam ◽  
Gawsia Wahidunnessa Chowdhury ◽  
Muntasir Akash ◽  
Md Anwarul Islam
Keyword(s):  
Relative Abundance ◽  
Migratory Birds ◽  
Anthropogenic Activities ◽  
Bird Species ◽  
Single Individual ◽  
Field Observations ◽  
Species Evenness ◽  
Number Of Species ◽  
Number Of Individuals ◽  
Near Threatened

A study on status and diversity of birds of Ramna Park, Dhaka, Bangladesh was conducted from July 2013 to March 2014. Data were collected through direct field observations where 6 days had been spent in every month in the field. A total of 50 species of birds belonging to 11 orders and 28 families were observed. Of the 50 species, 84% were residents and 16% migrants, 50% were passerines, 50% non-passerines. Passeriformes presented the highest number (25 species) of observed birds. Only Clamator jacobinus was recorded as summer migrant among the migratory birds. We found Psittacula eupatria considered as Near Threatened globally according to IUCN. Corvus splendens was the most common with the highest number of individuals in comparison to other bird species. We observed single individual of Clamator jacobinus followed by Psittacula eupatria and Apus pacificus throughout the study. Regarding the relative abundance, 18% species were very common, 30% common, 16% fairly common and 36% few. Calculating the Shannon-Wiener and Simpson’s indices of diversity and species evenness, we found maximum number of species and individuals in the month of December while minimum in the month of July. Anthropogenic activities such as festivals, random assemblies and gatherings, dumping of plastics, polythene and papers, noise from the vehicles were common inside and around the park, which may be threats to birds.Bangladesh J. Zool. 43(2): 291-301, 2015

scholarly journals Standardizing carabid pitfall catches for trapping effort; a meta-analysis

2020 ◽  
Author(s):  
Pavel Saska ◽  
David Makowski ◽  
David Bohan ◽  
Wopke van der Werf
Keyword(s):  
Meta Analysis ◽  
Carabid Beetles ◽  
Published Data ◽  
Power Exponent ◽  
List Type ◽  
Catch Per Unit Effort ◽  
Pitfall Trapping ◽  
Number Of Species ◽  
Activity Density ◽  
Abundance And Diversity

AbstractCarabid beetles (Coleoptera: Carabidae) provide important ecological services and are frequently used as a bio-indicator in monitoring environmental quality. The abundance and diversity of carabids is usually determined using pitfall trapping, but trap catches are difficult to compare between studies due to variation in trapping effort. The standardization of the catch for trapping effort has not been previously addressed in a global analysis of studies in the literature.The aims of this study are (i) to define a method for estimating the effect of trapping effort on the size of the pitfall catch, and (ii) to explore factors related to study designs, sampling method, study origin, and level of data aggregation to determine how these factors affect the catch per unit effort in pitfall trapping.We conducted a meta-analysis on the activity-density and diversity of carabids across studies, based on published data from Europe and North-America to analyse whether standardization of catch measurements might be possible. Data were extracted from 104 publications, spanning a period of 42 years.The total catch was proportional to the number of trap days, and ranged from 0.19-9.53 beetles/(trap day) across studies (95% range), with a mean of 1.33 beetles/(trap day). The number of species was allometrically related to the trapping effort defined as the product of the number of traps, their perimeter and the time of exposure in the field, and characterized by a power exponent of 0.25. Species richness ranged across studies from 2.30-13.18 species/(m day)0.25 (95% range) with a mean of 7.15 species/(m day)0.25. The size of the catch and the number of species were higher in crops with narrow as compared to wide rows. There was no significant change in abundance or diversity of carabids in arable land over the 42 years covered. We also found that increasing trapping effort may not yield more accurate results.The results show that it is possible to standardize activity-density-based catches and species diversity for trapping effort across studies using a power transformation, allowing meta-analysis of such data, e.g. to elucidate factors affecting abundance and diversity of the focal taxa.

IMMEDIATE AND LONG-TERM EFFECTS OF INSECTICIDE APPLICATION ON PARASITOIDS IN JACK PINE STANDS IN QUEBEC

1972 ◽  
Vol 104 (2) ◽  
pp. 263-270 ◽  
Author(s):  
Peter W. Price
Keyword(s):  
Relative Abundance ◽  
Jack Pine ◽  
Ground Vegetation ◽  
Long Term Effects ◽  
Aerial Application ◽  
Insecticide Application ◽  
Number Of Species ◽  
Adult Parasitoid ◽  
Pine Stands

AbstractParasitoid populations were sampled before, and for 4 years following, an aerial application of the insecticide phosphamidon to control a sawfly outbreak. Adult parasitoid mortality was high because of spraying, but a reservoir of parasitoids in host cocoons remained to repopulate the treated areas. In moister sites the number of species decreased and their relative abundance changed, but moderate numbers of parasitoids remained 4 years after spraying. In a dry site with little ground vegetation, none of the species present before spraying remained by the fourth year.

scholarly journals Singing in the suburbs: point count surveys efficiently reveal habitat associations for nocturnal Orthoptera across an urban-to-rural gradient

2020 ◽  
Vol 24 (6) ◽  
pp. 1031-1043
Author(s):  
Darin J. McNeil ◽  
Christina M. Grozinger
Keyword(s):  
Site Occupancy ◽  
Habitat Associations ◽  
Survey Method ◽  
Population Declines ◽  
Detection Rates ◽  
Point Count ◽  
Point Counts ◽  
Focal Species ◽  
Habitat Gradient ◽  
Count Surveys

Abstract As evidence for global insect population declines continues to amass, several studies have indicated that Orthoptera (grasshoppers, crickets, and katydids) are among the most threatened insect groups. Understanding Orthoptera populations across large spatial extents requires efficient survey protocols, however, many previously established methods are expensive and/or labor-intensive. One survey method widely employed in wildlife biology, the aural point count, may work well for crickets and katydids (suborder: Ensifera) because males produce conspicuous, species-specific mating calls. We conducted repeated point count surveys across an urban-to-rural gradient in central Pennsylvania. Occupancy analyses of ten focal species indicated that, although detection probability rates varied by species from 0.43 to 0.98, detection rates compounded over five visits such that all focal species achieved cumulative > 0.90. Factors associated with site occupancy varied among species with some positively associated with urbanization (e.g., Greater Anglewing, Microcentrum rhombifolium), some negatively associated with urbanization (e.g., Sword-bearing Conehead, Neoconocephalus ensiger), and others exhibiting constant occupancy across a habitat gradient (e.g., Common True Katydid, Pterophylla camellifolia). Our community-level analysis revealed that different species’ habitat associations interacted such that intermediate levels of urbanization (i.e., suburbs) hosted the highest number of species. Implications for insect conservation Ultimately, our analyses clearly support the concept that aural point counts paired with static occupancy modeling can serve as an important tool for monitoring night-singing Orthoptera populations. Applications of point count surveys by both researchers and citizen scientists may improve our understanding Ensifera populations and help in the global conservation of these threatened insects.

scholarly journals Factors influencing fall departure phenology in migratory birds that bred in northeastern North America

The Auk ◽  
2019 ◽  
Author(s):  
Émile Brisson-Curadeau ◽  
Kyle H Elliott ◽  
Pascal Côté
Keyword(s):  
North America ◽  
Short Distance ◽  
Migratory Birds ◽  
Breeding Habitat ◽  
Temperature Changes ◽  
Migration Timing ◽  
Warm Weather ◽  
Breeding Grounds ◽  
Timing Of Migration ◽  
Migrating Birds

Abstract The phenology of migrating birds is shifting with climate change. For instance, short-distance migrants wintering in temperate regions tend to delay their migration in fall during spells of warmer temperature. However, some species do not show strong shifts, and the factors determining which species will react to temperature changes by delaying their migration are poorly known. In addition, it is not known whether a slower migration or a postponed departure creates the observed delays in fall migration because most studies occur far south of the boreal breeding areas making it difficult to separate those 2 mechanisms. We used 22 yr of data at a northern observatory in eastern North America, at the southern edge of the boreal forest, to examine how 21 short-distance migrants responded to changing temperatures. We investigated if those species responding to temperature share life-history features (i.e. diet, size, total migration distance, breeding habitat, timing of migration). The period of migration in each species was, by far, the most important factor predicting the response of a species to temperature. Eight of the 13 species migrating in October changed their migration onset with temperature (usually by delaying migration by 1–2 days/°C), while the migration timing of none of the 8 species migrating in September was dependent on temperature. Furthermore, the absence of a greater migration delay by birds breeding farther from the study site (i.e. Arctic-breeding birds) suggests the mechanism is a postponed departure rather than a slower migration. We conclude that temperature variations in late fall influence the conditions on the breeding grounds, so that birds still present at that time benefit more from postponing their departure in warm weather.

scholarly journals New Baetidae (Insecta: Ephemeroptera) Records from Venezuela and Nymph Description of an UnnamedFallceonSpecies

2012 ◽  
Vol 2012 ◽  
pp. 1-6
Author(s):  
Paulo Vilela Cruz ◽  
Rafael Boldrini ◽  
Carlos F. Quinto ◽  
Hortencia Frontado
Keyword(s):  
South America ◽  
Species Identification ◽  
Number Of Species ◽  
First Time

The Ephemeroptera fauna in Venezuela is poorly known, as is also the case in others areas in South America. Recently, two studies increased from 33 to 50 the number of species recorded in Venezuela. The objective of the present study is to report for the first time in Venezuela the following species:Baetodes levis;Camelobaetidius edmundsi;Fallceonsp.;Mayobaetis ellenae.The nymph ofFallceonsp. is described, but is not named because adults were not reared to allow species identification; however, description of this nymph indicates the presence of this genus in South America.

scholarly journals Overcoming the challenges of measuring the abundance of a cryptic macropod: is a qualitative approach good enough?

2014 ◽  
Vol 41 (1) ◽  
pp. 84 ◽  
Author(s):  
Karlene Bain ◽  
Adrian Wayne ◽  
Roberta Bencini
Keyword(s):  
Population Size ◽  
Relative Abundance ◽  
Spatial Scales ◽  
Faecal Pellet ◽  
Survey Method ◽  
Population Abundance ◽  
Mark Recapture ◽  
Survey Technique ◽  
Threatened Taxa ◽  
Activity Indices

Context An understanding of population size and status is necessary for the implementation of appropriate conservation measures to recover threatened taxa. Mark–recapture studies at large spatial scales are impractical and expensive and a rapid survey technique is an attractive option to provide a measure of relative abundance for cryptic species, using indicators of activity. Aims The aim of our study was to use conventional methods for population estimation to calibrate a rapid survey technique for the quokka (Setonix brachyurus) in the southern forests of Western Australia, with a view to providing quantitative outcomes from this widely adopted monitoring approach. Methods We evaluated the accuracy of relative abundances obtained from the rapid survey technique by comparing them with abundance estimates obtained through established methods for the estimation of populations, including web-based mark–recapture and transect-based counts of activity indicators and sightings. Key results The rapid survey technique was effective at determining presence of quokkas but resulted in an over-estimation of population size because of inaccurate assumptions about occupancy and relative abundance of animals. An alternative survey method based on counts of fresh faecal-pellet groups was found to provide a more reliable and practical estimation of population abundance (R2 = 0.97). Conclusions Activity indices can be used to quantify population abundance, but only for indicators of activity that can be detected readily and for which freshness of activity can be determined. Implications Our findings suggest that a rapid survey based on activity indices can be used to evaluate quantitatively the population size of a species that is rare and potentially mobile at a landscape scale. The attraction of these techniques is that they provide a rapid and inexpensive survey option that is potentially applicable to any cryptic and/or threatened species and is practical for resource-constrained land managers.

scholarly journals Komunitas Makrozoobentos di Sungai Suir dalam Area Perkebunan Kelapa Sawit PT. Tidar Kerinci Agung

2018 ◽  
Vol 6 (2) ◽  
pp. 84
Author(s):  
Muhammad Syahid Ridho ◽  
Izmiarti Izmiarti ◽  
Jabang Nurdin
Keyword(s):  
Relative Abundance ◽  
Palm Oil ◽  
Sampling Technique ◽  
Survey Method ◽  
Chemical Measurements ◽  
Composition And Structure ◽  
Net Method ◽  
Study Sites ◽  
Macrozoobenthic Community ◽  
Research Show

The aim of this research was to know the composition and structure of macrozoobenthic community in Suir Stream at palm oil plantation area of PT. Tidar Kerinci Agung (TKA) has been conducted in February 2016 using survey method and purposive sampling technique in collecting data. Study sites consist of four stations based on condition around the stream. Macrozoobenthic community were sampled using surber net method with triplicate and accompanying physic-chemical measurements on each station. The results of this research show that 54 genera of macrozoobenthic were found consist of Insecta 44 genera, Oligochaeta 8 genera, Turbellaria and Gastropoda one genus respectively. The density of macrozoobenthic community range from 259.26-507.41 ind/m2 with average 381 ind/m2. The highest was found in station II dan the lowest was in station IV. The dominant genera (relative abundance > 10 %) in station I was Eukefferiella, station II Eukefferiella and Antocha, station III Tubificidae and Lumbriculus, station IV Eukiefferiella, Pseudocleon and Haplotaxis. The diversity of macrozoobenthic community was classified as moderate (H’= 1.25-2.94) and high equitability (E=0.54-0.84).

scholarly journals Combining point counts and autonomous recording units improves survey efficacy across elevational gradients on two continents

2021 ◽  
Author(s):  
Anna Drake ◽  
Devin de Zwaan ◽  
Tomás Altamirano ◽  
Scott Wilson ◽  
Kristina Hick ◽  
...  
Keyword(s):  
Detection Probability ◽  
Canopy Cover ◽  
Population Monitoring ◽  
Landscape Composition ◽  
Survey Method ◽  
Elevational Gradients ◽  
Point Counts ◽  
Time Costs ◽  
Mountain Habitats ◽  
Combined Methods

1. Accurate biodiversity and population monitoring is a requirement for effective conservation decision-making. Survey method bias is therefore a concern, particularly when research programs face logistical and cost limitations. 2. We employed point counts (PCs) and autonomous recording units (ARUs) to survey avian biodiversity across elevational gradients in comparable temperate mountain habitats at opposite ends of the Americas (9 mountains in British Columbia (BC), Canada and 10 in southern Chile). We compared detected species richness against multi-year species inventories and examined differences in detection probability by family. By incorporating time costs, we assessed the performance and efficiency of single vs. combined methods. 3. ARUs were predicted to capture ~92% of species present in BC but only ~58% in Chile, despite Chilean mountain communities being less diverse. Community, rather than landscape composition, appears to be the driver of this dramatic difference. Chilean communities contain less-vocal species, which ARUs missed. Further, 6/14 families in BC were better detected by ARUs while 11/11 families in Chile were better detected by PCs. Where survey conditions differentially impacted methods, PC detection varied over the morning and with canopy cover in BC and ARU detection probability mostly varied seasonally in Chile. Within a single year of monitoring, neither method alone was predicted to capture the full avian community, with the exception of ARUs in the alpine and subalpine of BC. PCs contributed little to detected diversity in BC, but including this method resulted in negligible increases in total time costs. Combining PCs with ARUs in Chile significantly increased species detections, again, for little cost. 4. Combined methods were among the most efficient and accurate approaches to capturing diversity. We recommend conducting observer point counts, where possible, when ARUs are deployed and retrieved, in order to capture additional diversity and flag methodology biases with minimal additional effort.

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