breeding distribution
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2021 ◽  
Author(s):  
◽  
Johannes Fischer

<p>Seabirds are one of the most threatened taxa on the planet. These species are also considered ecosystem engineers. Therefore, seabirds are of particular conservation interest. One of the most threatened seabirds is the critically endangered Whenua Hou Diving Petrel (Pelecanoides whenuahouensis; WHDP). The WHDP is restricted to a minute (0.018 km2) breeding colony on a single island — Whenua Hou (Codfish Island), Aotearoa (New Zealand). The WHDP population was estimated at 150 adults in 2005. The WHDP is threatened by storms and storm surges, which erode its breeding habitat (fragile foredunes), and potentially by competition for burrows with congenerics.  I aimed to inform suitable conservation strategies for the WHDP. I first quantified the efficacy of past conservation actions (eradications of invasive predators). I compiled burrow counts across four decades to estimate and compare population growth before and after predator eradications. I then investigated offshore threats using tracking data to quantify WHDP offshore distribution, behaviour, and overlap with commercial fishing efforts. Subsequently, I estimated the potential impact and success of WHDP translocations. Specifically, I combined capture-recapture, nest-monitoring, and count data in an integrated population model (IPM) to predict the impact of harvesting chicks for translocations on the source population and to project the establishment of a second population. I then informed future translocation protocols using nest-monitoring data to quantify nest survival and breeding biology. Finally, I tested if WHDP presence had a positive influence on unrelated species groups. I counted two skink species at sites with and without burrows and used occupancy modelling to quantify the influence WHDP burrows had on skink occurrence.  Estimates of population growth before and after predator eradications illustrated that WHDP population growth remained comparatively low and unaffected by this conservation strategy. Therefore, additional interventions are required. WHDP tracking revealed that the non-breeding distribution did not overlap with commercial fishing efforts. However, considerable fishing efforts were present within the breeding distribution. Despite these findings, onshore threats remain present and conservation strategies aimed at addressing terrestrial threats may be more feasible. Results from my IPM showed that translocations could successfully establish a second WHDP population without impacting the source excessively, provided translocation cohorts remain small and translocations are repeated over long time periods (5-10 years). Nest survival was not clearly influenced by interannual variation, distance to sea, and intra- or interspecific competition. Furthermore, I informed future translocation protocols by identifying the preferred harvest window, measurements of ideal translocation candidates, and feeding regimes. Occurrence of one skink species was 114% higher at sites with burrows than at sites without, suggesting that WHDP presence benefits unrelated species.  The information provided in this thesis facilitates the identification of future management strategies for this critically endangered species. However, future conservation management of the WHDP should be based on structured decision-making frameworks that apply iterative adaptive management loops and must acknowledge the unique position of tangata whenua (people of the land). This approach could address the consequences and trade-offs of each alternative, account for uncertainty, facilitate the decolonisation of conservation biology, and would ultimately result in the best potential outcome of the target species in a truly integrated fashion.</p>


2021 ◽  
Author(s):  
◽  
Johannes Fischer

<p>Seabirds are one of the most threatened taxa on the planet. These species are also considered ecosystem engineers. Therefore, seabirds are of particular conservation interest. One of the most threatened seabirds is the critically endangered Whenua Hou Diving Petrel (Pelecanoides whenuahouensis; WHDP). The WHDP is restricted to a minute (0.018 km2) breeding colony on a single island — Whenua Hou (Codfish Island), Aotearoa (New Zealand). The WHDP population was estimated at 150 adults in 2005. The WHDP is threatened by storms and storm surges, which erode its breeding habitat (fragile foredunes), and potentially by competition for burrows with congenerics.  I aimed to inform suitable conservation strategies for the WHDP. I first quantified the efficacy of past conservation actions (eradications of invasive predators). I compiled burrow counts across four decades to estimate and compare population growth before and after predator eradications. I then investigated offshore threats using tracking data to quantify WHDP offshore distribution, behaviour, and overlap with commercial fishing efforts. Subsequently, I estimated the potential impact and success of WHDP translocations. Specifically, I combined capture-recapture, nest-monitoring, and count data in an integrated population model (IPM) to predict the impact of harvesting chicks for translocations on the source population and to project the establishment of a second population. I then informed future translocation protocols using nest-monitoring data to quantify nest survival and breeding biology. Finally, I tested if WHDP presence had a positive influence on unrelated species groups. I counted two skink species at sites with and without burrows and used occupancy modelling to quantify the influence WHDP burrows had on skink occurrence.  Estimates of population growth before and after predator eradications illustrated that WHDP population growth remained comparatively low and unaffected by this conservation strategy. Therefore, additional interventions are required. WHDP tracking revealed that the non-breeding distribution did not overlap with commercial fishing efforts. However, considerable fishing efforts were present within the breeding distribution. Despite these findings, onshore threats remain present and conservation strategies aimed at addressing terrestrial threats may be more feasible. Results from my IPM showed that translocations could successfully establish a second WHDP population without impacting the source excessively, provided translocation cohorts remain small and translocations are repeated over long time periods (5-10 years). Nest survival was not clearly influenced by interannual variation, distance to sea, and intra- or interspecific competition. Furthermore, I informed future translocation protocols by identifying the preferred harvest window, measurements of ideal translocation candidates, and feeding regimes. Occurrence of one skink species was 114% higher at sites with burrows than at sites without, suggesting that WHDP presence benefits unrelated species.  The information provided in this thesis facilitates the identification of future management strategies for this critically endangered species. However, future conservation management of the WHDP should be based on structured decision-making frameworks that apply iterative adaptive management loops and must acknowledge the unique position of tangata whenua (people of the land). This approach could address the consequences and trade-offs of each alternative, account for uncertainty, facilitate the decolonisation of conservation biology, and would ultimately result in the best potential outcome of the target species in a truly integrated fashion.</p>


2021 ◽  
Author(s):  
Lily Donzeiser ◽  
Maggie MacPherson

In the 21st century, climate change is threatening the populations of many species with extinction (Parmesan &amp; Yohe, 2003). Migratory species, some of whose breeding ranges are located in areas of fast-paced change, are at risk (Møller et al., 2008; Sander et al., 2020). We propose an assessment of the spatial response to climate change of such a species, the Scarlet Tanager (Piranga olivacea). P. olivacea migrate to the northern regions of North America (Mowbray, 2020), where rapid climate change may threaten the species’ suitability to their historical breeding areas. To test whether P. olivacea are responding spatially to climate change, we will use a two pronged approach looking at occurrence and morphological change from across their breeding range over time. First, we will assess spatial responses to climate change by comparing historical breeding occurrence and climate data (March-August, ca. 70-50 years ago; 1950-1970), to current occurrence data (years 2000-2020), to build a forecast of potential future breeding distribution for this species using Maxent software (Phillips et al., 2018). Breeding season occurrence data for historical and current time periods will be sourced from museum records from www.gbif.org, and will be matched with environmental data (i.e., temperature, precipitation,land cover). Recent research has supported that migratory birds are growing longer wings in response to climate change, presumably under selection pressure to support improved flight efficiency for migrating longer distances to access appropriate environmental conditions for breeding (Weeks et al., 2020). We will assess morphological changes over time in breeding P. olivacea in response to predictions under climate change hypotheses by measuring museum specimens from the American Museum of Natural History and the Louisiana State University Museum of Natural Science. We intend to infer whether P. olivacea possesses adequate adaptive potential to keep pace with relevant climate change metrics, and more broadly whether climate change is driving selection on morphology to reach a more northern breeding distribution for this species. If the historical distribution is explained by climate variables but P. olivacea has not shifted its breeding range or exhibited morphological shifts, this may be evidence of low adaptive capacity. Climate, morphological and occurrence data will be analyzed to determine the suitability of P. olivacea in its current breeding range, as well as alternative responses including shifts in the species’ reproductive windows. Our data will include bill length, mass, and hand-wing index variables for morphological analyses, while precipitation, temperature, and land cover will be included in the environmental datasets. Statistical analysis will be run by the American Museum of Natural History’s Maxent software, v. 3.4.4. Results will provide support for conservation efforts for forest-dwelling long distance migrant birds threatened by climate change, and can aid in the understanding of climate change’s effects on migratory species as a whole.


Author(s):  
Per Alström ◽  
Gombobaatar Sundev

Abstract The eastern subspecies of Greater Short-toed Lark Calandrella brachydactyla dukhunensis has recently been considered a separate species, Calandrella dukhunensis, by several authors based on molecular data. We present supporting evidence for this treatment based on studies of morphology, vocalisations and song-flight, and also present new data on other aspects of its biology based on field studies. We show that its breeding distribution is considerably smaller than previously thought, and is restricted to the eastern half of Mongolia and, marginally, neighbouring parts of China and perhaps Russia.


Check List ◽  
2020 ◽  
Vol 16 (4) ◽  
pp. 933-937
Author(s):  
John P. Vanek ◽  
Jess Fliginger ◽  
Richard B. King

American Badgers, Taxidea taxus (Schreber, 1777) are poorly studied relative to other North American carnivores. We&nbsp;report on observations of American Badgers within a restored tallgrass prairie ecosystem owned and managed by The&nbsp;Nature Conservancy in Illinois. We documented badgers at six camera locations, including two prairie restorations restored&nbsp;from row crop agriculture in 2002 and 2015. In addition, we confirmed breeding activity in Ogle County, filling&nbsp;a gap in the known breeding distribution of American Badgers in Illinois. We provide context for these observations&nbsp;and suggestions for future research.


2020 ◽  
Vol 140 (2) ◽  
pp. 164
Author(s):  
Christopher J. Sharpe ◽  
Sandra B. Giner F. ◽  
Adriana Rodríguez-Ferraro ◽  
Jhonathan Miranda ◽  
Lermith Torres ◽  
...  

The counts of breeding Jackdaws were made in Kharkiv City, Ukraine in April – early June of 2016–2017. We estimated the breeding density among different habitat types. For such a purpose the city area was divided into 0.25 km² squares (n = 1354) and we estimated the numbers of pairs within the boundaries of 40 squares (QGIS program was used to choose randomly these squares). The surveys were made in April–May (19 squares) and early June (4 squares) in 2016 and April–May (10 squares) and early June (7 squares) in 2017. The surveys were made within main habitat types such as area of residential blocks of flats, residential area (1–2-storey buildings), industrial area, forest zone, park zone and undeveloped urban areas. The data on the area occupied by every major habitat type (in km²) were calculated by QGIS program. The 90 % of the territory of Kharkiv City was analysed, except water reservoirs and traffic way areas. The data of the surveys were extrapolated across areas of the same habitat types. Also we have searched for Jackdaw colonies within the boundaries of Kharkiv City to take these data into account. According to the collected data the Jackdaw prefers to nest in crevices of old 3–5-level buildings at built-up districts or in round cross-sections of posts at blocks-of-flats areas. Thus the mean density here was 22 pairs/km². The mean density of Jackdaw in industrial areas was 15 pairs/km², in undeveloped urban areas – 1.2 pairs/km², and in residential area (1–2-storey buildings) – 0.7 pairs/km². The total number of breeding Jackdaws in Kharkiv City was estimated at 2325 to 2630 pairs. The mean density of Jackdaws was 7.5 pairs/km². Taking into account the moderate decline in the population of the Jackdaws in some European countries (although in general the population trend remains stable within the continent), and the lack of the surveys of the breeding distribution and numbers of Jackdaws in large cities of the Eastern Ukraine, it’s reasonable to use our data as an optimal starting point for the monitoring of the regional population trend of the species. The data of 2016 year survey were used in European Breeding Bird Atlas 2 (EBBA2) programme (square 37UCR2).


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