Estimating conservation metrics from atlas data: the case of southern African endemic birds

SummaryThe robust assessment of conservation status increasingly requires population metrics for species that may be little-researched, with no prospect of immediate improvement, but for which citizen science atlas data may exist. We explore the potential for bird atlas data to generate population metrics of use in red data assessment, using the endemic and near-endemic birds of southern Africa. This region, defined here as South Africa, Lesotho and Swaziland, is home to a large number of endemic bird species and an active atlas project. The Southern African Bird Atlas Projects (SABAP) 1 and 2 are large-scale citizen science data sets, consisting of hundreds of thousands of bird checklists and > 10 million bird occurrence records on a grid across the subcontinent. These data contain detailed information on species’ distributions and population change. For conservationists, metrics that guide decisions on the conservation status of a species for red listing can be obtained from SABAP, including range size, range change, population change, and range connectivity (fragmentation). We present a range of conservation metrics for these bird species, focusing on population change metrics together with an associated statistical confidence metric. Population change metrics correlate with change metrics calculated from dynamic occupancy modelling for a set of 191 common species. We identify four species with neither international nor local threatened status, yet for which bird atlas data suggest alarming declines, and two species with threatened status for which our metrics suggest could be reconsidered. A standardised approach to deciding the conservation status of a species is useful so that charismatic or flagship species do not receive disproportionate attention, although ultimately conservation status of any species must always be a consultative process.

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Use of Citizen Science Data for Characterizing Patterns and Drivers of Avian Altitudinal Migration

Biodiversity Information Science and Standards ◽

10.3897/biss.3.36223 ◽

2019 ◽

Vol 3 ◽

Author(s):

Pei-Yu Tsai ◽

Chie-Jen Ko ◽

Ya-Jung Lu ◽

Chia Hsieh ◽

Mao-Ning Tuanmu

Keyword(s):

Citizen Science ◽

Environmental Changes ◽

Global Analysis ◽

Research Question ◽

Bird Species ◽

Migration Behavior ◽

Mountain Regions ◽

Science Data ◽

Essential Information ◽

Altitudinal Migration

Altitudinal migration, the seasonal and repeateing movement of animal individuals between breeding and non-breeding areas at different elevations, is a common and important but understudied behavior in birds. Difficulty in characterizing avian altitudinal migration has prevented a comprehensive understanding of both patterns and drivers of this behavior. To fill this knowledge gap, we investigated altitudinal migration patterns and underlying mechanisms for a major proportion (~70%) of an entire resident bird community on a subtropical island with an almost 4000-m elevational gradient. We quantified migration tendency of individual bird species based on the seasonal shift in the elevational distribution of their occurrence records in the eBird database. We then built phylogeny-controlled regression models to examine the associations between the birds’ migration tendencies and their functional traits to test major hypotheses on the mechanisms of altitudinal migration. The results showed a common but variable altitudinal migration behavior among the 118 species examined, with 40 and 11 species conducting post-breeding downhill and uphill migration, respectively. The species that have a narrower thermal tolerance range, can tolerate lower temperatures, have a smaller body size, have a more diverse or invertebrate-rich diet, or use an open nest had a higher downhill migration tendency. In contrast, no traits examined showed consistent associations with the uphill migration tendency. This suggests that post-breeding downhill and uphill migrations are driven by different processes and current hypotheses can only explain the former, but not the latter. This relatively comprehensive study demonstrated the power of citizen science data to provide new insights into an old research question from a novel perspective. Using the same approach, we are investigating the behavior in mountain regions around the world. With the global analysis, we will be able to understand the general patterns and mechanisms of avian altitudinal migration and also investigate their variation among mountain regions in different climate zones. In the face of rapid environmental changes in mountain ecosystems, the approach used in this study may also provide essential information for the conservation of mountainous biodiversity.

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Exotic parrots breeding in urban tree cavities: nesting requirements, geographic distribution, and potential impacts on cavity nesting birds in southeast Florida

Avian Research ◽

10.1186/s40657-019-0176-3 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 4

Author(s):

Joshua M. Diamond ◽

Michael S. Ross

Keyword(s):

Citizen Science ◽

Geographic Distribution ◽

Urban Areas ◽

Interference Competition ◽

Bird Species ◽

Inspection System ◽

Dade County ◽

Science Data ◽

Tree Cavities ◽

Cavity Nesting

Abstract Background Exotic parrots have established breeding populations in southeast Florida, including several species that nest in tree cavities. We aimed to determine the species identity, nest site requirements, relative nest abundance, geographic distribution, and interactions of parrots with native cavity-nesting bird species. Methods We searched Miami-Dade County, Florida, and nearby areas for natural cavities and holes excavated by woodpeckers, recording attributes of potential nest trees. We inspected all cavities with an elevated video inspection system to determine occupancy by parrots or other birds. We mapped nearly 4000 citizen science observations of parrots in our study area corresponding to our study period, and used these to construct range maps, comparing them to our nesting observations. Results Not all parrots reported or observed in our study area were actively breeding. Some parrots were observed at tree cavities, which previous studies have suggested is evidence of reproduction, but our inspections with an elevated video inspection system suggest they never initiated nesting attempts. Several parrot species did successfully nest in tree cavities, Red-masked Parakeets (Psittacara erythrogenys) and Orange-winged Parrots (Amazona amazonica) being the most common (n = 7 and 6 nests, respectively). These two parrots had similar nesting requirements, but Orange-winged Parrots use nests with larger entrance holes, which they often enlarge. Geographic analysis of nests combined with citizen science data indicate that parrots are limited to developed areas. The most common parrots were less abundant cavity nesters than the native birds which persist in Miami’s urban areas, and far less abundant than the invasive European Starling (Sturnus vulgaris). Conclusions Exotic parrots breeding elsewhere in the world have harmed native cavity-nesting birds through interference competition, but competitive interference in southeast Florida is minimized by the urban affinities of parrots in this region. The relative abundance and geographic distribution suggest that these parrots are unlikely to invade adjacent wilderness areas.

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Estimating disease vector population size from citizen science data

Journal of The Royal Society Interface ◽

10.1098/rsif.2021.0610 ◽

2021 ◽

Vol 18 (184) ◽

Author(s):

Tam Tran ◽

W. Tanner Porter ◽

Daniel J. Salkeld ◽

Melissa A. Prusinski ◽

Shane T. Jensen ◽

...

Keyword(s):

Data Collection ◽

Citizen Science ◽

Large Scale ◽

Species Abundance ◽

Natural World ◽

Tick Population ◽

Science Data ◽

Tick Abundance ◽

Vector Population ◽

Public Datasets

Citizen science projects have the potential to address hypotheses requiring extremely large datasets that cannot be collected with the financial and labour constraints of most scientific projects. Data collection by the general public could expand the scope of scientific enquiry if these data accurately capture the system under study. However, data collection inconsistencies by the untrained public may result in biased datasets that do not accurately represent the natural world. In this paper, we harness the availability of scientific and public datasets of the Lyme disease tick vector to identify and account for biases in citizen science tick collections. Estimates of tick abundance from the citizen science dataset correspond moderately with estimates from direct surveillance but exhibit consistent biases. These biases can be mitigated by including factors that may impact collector participation or effort in statistical models, which, in turn, result in more accurate estimates of tick population sizes. Accounting for collection biases within large-scale, public participation datasets could update species abundance maps and facilitate using the wealth of citizen science data to answer scientific questions at scales that are not feasible with traditional datasets.

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Winners and losers over 35 years of dragonfly and damselfly distributional change in Germany

10.1101/2020.08.03.234104 ◽

2020 ◽

Author(s):

D.E Bowler ◽

D. Eichenberg ◽

K.J. Conze ◽

F. Suhling ◽

K. Baumann ◽

...

Keyword(s):

Citizen Science ◽

Large Scale ◽

Positive Trend ◽

Science Data ◽

Running Water ◽

Distributional Change ◽

Novel Approach ◽

Occupancy Detection ◽

Declining Species

AbstractRecent studies suggest insect declines in parts of Europe; however, the generality of these trends across different taxa and regions remains unclear. Standardized data are not available to assess large-scale, long-term changes for most insect groups but opportunistic citizen science data is widespread for some taxa. We compiled over 1 million occurrence records of Odonata (dragonflies and damselflies) from different regional databases across Germany. We used occupancy-detection models to estimate annual distributional changes between 1980 and 2016 for each species. We related species attributes to changes in the species’ distributions and inferred possible drivers of change. Species showing increases were generally warm-adapted species and/or running water species while species showing decreases were cold-adapted species using standing water habitats such as bogs. We developed a novel approach using time-series clustering to identify groups of species with similar patterns of temporal change. Using this method, we defined five typical patterns of change for Odonata – each associated with a specific combination of species attributes. Overall, trends in Odonata provide mixed news – improved water quality, coupled with positive impacts of climate change, could explain the positive trend status of many species. At the same time, declining species point to conservation challenges associated with habitat loss and degradation. Our study demonstrates the great value of citizen science data for assessing large-scale distributional change and conservation decision-making.

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Assessing conservation status of resident and migrant birds on Hispaniola with constant-effort mist-netting

10.7287/peerj.preprints.1368v1 ◽

2015 ◽

Author(s):

John D Lloyd ◽

Chris C Rimmer ◽

Kent P McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January – March from 1997 – 2010. We found evidence of steep declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microlegia palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenolegia montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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Assessing conservation status of resident and migrant birds on Hispaniola with mist-netting

PeerJ ◽

10.7717/peerj.1541 ◽

2016 ◽

Vol 3 ◽

pp. e1541 ◽

Cited By ~ 2

Author(s):

John D. Lloyd ◽

Christopher C. Rimmer ◽

Kent P. McFarland

Keyword(s):

Population Change ◽

Conservation Status ◽

Capture Rate ◽

Temporal Trends ◽

Bird Species ◽

Quantitative Information ◽

Neotropical Migrant ◽

Migrant Birds ◽

Conservation Assessments ◽

Capture Rates

We analyzed temporal trends in mist-net capture rates of resident (n= 8) and overwintering Nearctic-Neotropical migrant (n= 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January–March from 1997 to 2010. We found evidence of declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microligea palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenoligea montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.

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