Homeward bound: canopy cover and species identity influence non-breeding season homing success and speed in forest birds

Abstract Background Efficient and safe movement is fundamental for wild birds to thrive in their environments. For arboreal forest animals, especially birds, canopy cover has a large impact on birds’ daily movements and is a crucial component of conservation strategies seeking to retain avian population in disturbed or urban habitats. Methods We translocated woodland bird species utilizing different forest strata during two non-breeding seasons in Gainesville, FL, USA. We used linear model and generalized linear model to examine the effects of canopy cover and species identity on homing success and speed. Results Among our study species of Tufted Titmouse (Baeolophus bicolor), Carolina Chickadee (Poecile carolinensis), and Northern Cardinal (Cardinalis cardinalis), we found that Carolina Chickadees and Tufted Titmice were more likely to return than Northern Cardinals. Among birds that successfully returned, homing speed is significantly affected by forest canopy cover and species identity (titmice had higher homing speed than cardinals). Birds return much faster in landscape with higher canopy cover. Conclusions This study presented evidence of species identity’s effect on homing success and speed in common feeder bird species in Southeast US and provided further evidence that bird movements in the suburban land cover are constrained by low canopy cover.

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Nest site selection and reproductive parameters of the threatened Atlantic Royal Flycatcher (Onychorhynchus swainsoni) and their significance for conservation

Avian Research ◽

10.1186/s40657-020-00237-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Daniel F. Perrella ◽

Paulo V. Q. Zima ◽

Mercival R. Francisco

Keyword(s):

Atlantic Forest ◽

Site Selection ◽

Nest Site ◽

Bird Species ◽

Canopy Cover ◽

Nest Site Selection ◽

Breeding Biology ◽

Conservation Strategies ◽

Vegetation Density ◽

Habitat Specificity

Abstract Background Patterns of rarity can be explained by reproductive rates, levels of endemism, and habitat specificity, and knowledge on these parameters is important to understand the levels of vulnerability of each species and to formulate conservation strategies. Here, we studied nest-site selection and breeding biology of the Atlantic Royal Flycatcher (Onychorhynchus swainsoni), a poorly known vulnerable bird endemic to the Brazilian Atlantic Forest. Methods We addressed nest site selection in three different levels: first, we searched for nests near and far from water to investigate whether birds could select water proximities to construct nests; second, we examined if they could select certain streams in detriment of others, and we analyzed the characteristics of used and non-used streams, and third, in streams in which nests were found, we addressed nest site selectivity by comparing a number of parameters between nest sites and random sites. Further, we provide information on breeding biology parameters related to annual fecundity. Results During five breeding seasons, we found 23 nests in a well-preserved forest continuum. All of the nests were constructed above water, and they were found in streams that were about 4 m in width, instead of smaller streams with about 1.5 m in width. Modeling analyses revealed that within the used streams, nests were constructed in sites with lower vegetation density in relation to random points, while stream width, water speed, and canopy cover presented no significant correlation. Atlantic Royal Flycatchers in our study had a 22-day incubation period and 24 to 27-day nestling period. Overall nest survival was comparatively high (62%), but clutch size was small (N = 2 eggs) and double-brooding was unlikely, which resulted in a low annual fecundity (1.4 ± 0.9 fledglings per reproductive female). Along the nesting streams, we found an average of 1.62 ± 0.07 breeding pairs/km. Conclusions These data suggest that nesting habitat specificity and low annual fecundity are among the factors contributing to the rarity of the Atlantic Royal Flycatcher in large forest continuums and to its absence in fragmented environments. It reinforces the importance of large well-preserved forest continuums for the conservation of habitat specialist Atlantic Forest bird species.

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Nest cameras do not affect nest survival in a meadow-nesting shorebird

Bird Conservation International ◽

10.1017/s0959270920000659 ◽

2020 ◽

pp. 1-10

Author(s):

VOLKER SALEWSKI ◽

LUIS SCHMIDT

Keyword(s):

Nest Survival ◽

Bird Species ◽

Conservation Strategies ◽

Survival Models ◽

Northern Germany ◽

Term Study ◽

Long Term Study ◽

Limosa Limosa ◽

Study Sites

Summary Identifying the fate of birds’ nests and the causes of breeding failure is often crucial for the development of conservation strategies for threatened species. However, collecting these data by repeatedly visiting nests might itself contribute to nest failure or bias. To solve this dilemma, automatic cameras have increasingly been used as a time-efficient means for nest monitoring. Here, we consider whether the use of cameras itself may influence hatching success of nests of the Black-tailed Godwit Limosa limosa at two long-term study sites in northern Germany. Annually between 2013 and 2019, cameras were used to monitor godwit nests. In 2014 and 2019, nests were randomly equipped with cameras or not, and nest survival checked independently of the cameras. Nest-survival models indicated that survival probabilities varied between years, sites and with time of the season, but were unaffected by the presence of cameras. Even though predation is the main cause of hatching failure in our study system, we conclude that predators did not learn to associate cameras with food either when the cameras were initially installed or after they had been used for several years. Cameras were thus an effective and non-deleterious tool to collect data for conservation in this case. As other bird species may react differently to cameras at their nests, and as other sets of predators may differ in their ability to associate cameras with food, the effect of cameras on breeding success should be carefully monitored when they are used in a new study system.

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Estimating Forest Canopy Cover by Multiscale Remote Sensing in Northeast Jiangxi, China

Land ◽

10.3390/land10040433 ◽

2021 ◽

Vol 10 (4) ◽

pp. 433

Author(s):

Xiaolan Huang ◽

Weicheng Wu ◽

Tingting Shen ◽

Lifeng Xie ◽

Yaozu Qin ◽

...

Keyword(s):

Remote Sensing ◽

Large Scale ◽

Forest Canopy ◽

Canopy Cover ◽

Google Earth ◽

Tree Canopy ◽

Landsat Data ◽

High Resolution Data ◽

Modis Ndvi ◽

Tree Canopy Cover

This research was focused on estimation of tree canopy cover (CC) by multiscale remote sensing in south China. The key aim is to establish the relationship between CC and woody NDVI (NDVIW) or to build a CC-NDVIW model taking northeast Jiangxi as an example. Based on field CC measurements, this research used Google Earth as a complementary source to measure CC. In total, 63 sample plots of CC were created, among which 45 were applied for modeling and the remaining 18 were employed for verification. In order to ascertain the ratio R of NDVIW to the satellite observed NDVI, a 20-year time-series MODIS NDVI dataset was utilized for decomposition to obtain the NDVIW component, and then the ratio R was calculated with the equation R = (NDVIW/NDVI) *100%, respectively, for forest (CC >60%), medium woodland (CC = 25–60%) and sparse woodland (CC 1–25%). Landsat TM and OLI images that had been orthorectified by the provider USGS were atmospherically corrected using the COST model and used to derive NDVIL. R was multiplied for the NDVIL image to extract the woody NDVI (NDVIWL) from Landsat data for each of these plots. The 45 plots of CC data were linearly fitted to the NDVIWL, and a model with CC = 103.843 NDVIW + 6.157 (R2 = 0.881) was obtained. This equation was applied to predict CC at the 18 verification plots and a good agreement was found (R2 = 0.897). This validated CC-NDVIW model was further applied to the woody NDVI of forest, medium woodland and sparse woodland derived from Landsat data for regional CC estimation. An independent group of 24 measured plots was utilized for validation of the results, and an accuracy of 83.0% was obtained. Thence, the developed model has high predictivity and is suitable for large-scale estimation of CC using high-resolution data.

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Forest canopy cover analysis using UAS lidar

2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS) ◽

10.1109/igarss.2017.8127596 ◽

2017 ◽

Author(s):

Qingwang Liu ◽

Shiming Li ◽

Kailong Hu ◽

Yong Pang ◽

Zengyuan Li

Keyword(s):

Forest Canopy ◽

Canopy Cover

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Synchronous retrieval of forest canopy cover by airborn LiDAR and optical remote sensing

2010 IEEE International Geoscience and Remote Sensing Symposium ◽

10.1109/igarss.2010.5649315 ◽

2010 ◽

Author(s):

Chunxiang Cao ◽

Min Xu ◽

Yunfei Bao ◽

Hao Zhang

Keyword(s):

Remote Sensing ◽

Forest Canopy ◽

Canopy Cover ◽

Optical Remote Sensing

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The accuracy of large-area forest canopy cover estimation using Landsat in boreal region

International Journal of Applied Earth Observation and Geoinformation ◽

10.1016/j.jag.2016.08.009 ◽

2016 ◽

Vol 53 ◽

pp. 118-127 ◽

Cited By ~ 11

Author(s):

Hadi ◽

Lauri Korhonen ◽

Aarne Hovi ◽

Petri Rönnholm ◽

Miina Rautiainen

Keyword(s):

Forest Canopy ◽

Canopy Cover ◽

Large Area ◽

Boreal Region

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Estimation of forest canopy cover: a comparison of field measurement techniques

Silva Fennica ◽

10.14214/sf.315 ◽

2006 ◽

Vol 40 (4) ◽

Cited By ~ 141

Author(s):

Lauri Korhonen ◽

Kari Korhonen ◽

Miina Rautiainen ◽

Pauline Stenberg

Keyword(s):

Field Measurement ◽

Forest Canopy ◽

Measurement Techniques ◽

Canopy Cover

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Detecting Long-Term Urban Forest Cover Change and Impacts of Natural Disasters Using High-Resolution Aerial Images and LiDAR Data

Remote Sensing ◽

10.3390/rs12111820 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1820

Author(s):

Raoul Blackman ◽

Fei Yuan

Keyword(s):

Remote Sensing ◽

Ecosystem Services ◽

Forest Canopy ◽

High Spatial Resolution ◽

Urban Forest ◽

Urban Canopy ◽

Canopy Cover ◽

Random Point ◽

Aerial Images ◽

Lidar Data

Urban forests provide ecosystem services; tree canopy cover is the basic quantification of ecosystem services. Ground assessment of the urban forest is limited; with continued refinement, remote sensing can become an essential tool for analyzing the urban forest. This study addresses three research questions that are essential for urban forest management using remote sensing: (1) Can object-based image analysis (OBIA) and non-image classification methods (such as random point-based evaluation) accurately determine urban canopy coverage using high-spatial-resolution aerial images? (2) Is it possible to assess the impact of natural disturbances in addition to other factors (such as urban development) on urban canopy changes in the classification map created by OBIA? (3) How can we use Light Detection and Ranging (LiDAR) data and technology to extract urban canopy metrics accurately and effectively? The urban forest canopy area and location within the City of St Peter, Minnesota (MN) boundary between 1938 and 2019 were defined using both OBIA and random-point-based methods with high-spatial-resolution aerial images. Impacts of natural disasters, such as the 1998 tornado and tree diseases, on the urban canopy cover area, were examined. Finally, LiDAR data was used to determine the height, density, crown area, diameter, and volume of the urban forest canopy. Both OBIA and random-point methods gave accurate results of canopy coverages. The OBIA is relatively more time-consuming and requires specialist knowledge, whereas the random-point-based method only shows the total coverage of the classes without locational information. Canopy change caused by tornado was discernible in the canopy OBIA-based classification maps while the change due to diseases was undetectable. To accurately exact urban canopy metrics besides tree locations, dense LiDAR point cloud data collected at the leaf-on season as well as algorithms or software developed specifically for urban forest analysis using LiDAR data are needed.

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Diversity, Uses, and Threats in the Ghodaghodi Lake Complex, a Ramsar Site in Western Lowland Nepal

ISRN Biodiversity ◽

10.1155/2014/680102 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Pramod Lamsal ◽

Krishna Prasad Pant ◽

Lalit Kumar ◽

Kishor Atreya

Keyword(s):

Aquatic Macrophytes ◽

Irrigation System ◽

Local Level ◽

Bird Species ◽

Habitat Destruction ◽

Population Pressure ◽

Conservation Strategies ◽

Seepage Water ◽

Ramsar Site ◽

Anthropogenic Threats

This study documents aquatic and terrestrial/riparian biodiversity in an anthropogenically disturbed Ramsar site, the Ghodaghodi Lake complex, in the Western Nepal surveyed during the summer season (March-April) of 2007. The study site comprises three major interconnected lakes: Ghodaghodi (138 ha), Nakharodi (70 ha), and Bainshwa (10 ha). Five transect lines for aquatic macrophytes and three transect lines and 37 sampling plots were laid to sample terrestrial/riparian plants, birds, and animals. Five sample plots were established for fish and aquatic bird. A total of 45 species of aquatic macrophytes, 54 species of terrestrial/riparian vegetation, 19 fish species, 41 bird species, 17 mammals (endangered and vulnerable), and 5 reptiles (critically endangered, vulnerable, and near threatened) were recorded at the lake complex. Local people have used most of the aquatic and terrestrial plants for different purposes while many of the potential medicinal plant species were still untapped. Persistent anthropogenic threats, like excessive harvesting and poaching, habitat destruction—population pressure, forest fragmentation, siltation, fertilizer and pesticide seepage, water pollution, overgrazing, and unmanaged irrigation system found over the lake complex, endangered the existing biodiversity. The suggested remedial measures are further exploration of medicinal potential, prioritization of in situ biodiversity conservation strategies, and implementation of awareness program at local level against anthropogenic threats.

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