Urban Noise and Surrounding City Morphology Influence Green Space Occupancy by Native Birds in a Mediterranean-type South American Metropolis

Urban green spaces provide natural habitat for birds in urban landscapes, yet the effects of noise and surrounding urban morphology on bird community structure and distribution are not well understood in Latin America, the second most urbanized region in the world. Santiago of Chile is the single city belonging to the Mediterranean ecosystem in South America and is subject to extensive urbanization as seen throughout Latin America. We examined the role of 65 urban green spaces (6 large: PAR and 59 small: SGS) in harboring native birds during winter 2019, analyzing the quality of green areas in terms of vegetation (i.e. NDVI, native vegetation, and tree cover), exotic bird species, noise levels, and surrounding urban matrix (i.e. building height and cover). Significantly higher noise levels were detected in SGS, along with significantly greater exotic bird (n=4) richness and abundance than PAR, which possessed significantly greater native bird (n=25) richness and abundance. Native birds were more abundant than exotic birds in green spaces with average noise levels < 52 dB and average NDVI > 0.5. Occupancy models indicate that green space occupancy by 50% of modeled native bird species was influenced by maximum noise levels, playing a larger role than vegetation (30%) and the urban matrix (0%). We stress the importance of developing networks of large green spaces in rapidly urbanizing regions, with abundant tree cover, surrounded by smaller urban morphology, and regulating noise levels to ensure the conservation of native bird communities in cities, particularly those that are threatened.

Roadsides are key habitats for birds in the Argentine Pampas: conservation and management implications

Summary Unexploited public areas such as roadsides could provide habitat to help preserve biodiversity in South America, as in other regions. Our objective was to determine the importance of the roadsides of the Argentine Pampas for native birds and to suggest management strategies. We surveyed birds inhabiting roadsides in all seasons and determined whether roadsides were used as habitat. We recorded a total of 95 species on roadsides, which represents 55% of those species described from the area. Species included specialists of grassland, wetland and woodland, 4 vulnerable species and 19 declining species. Bird richness decreased in winter, as well as grassland specialists’ abundances. Most individuals used roadsides for foraging and performing reproduction-related behaviours, mainly on native trees; these and tall grass were the main substrates. We conclude that many species of birds use the habitat provided by roadsides, and we recommend management strategies such as favouring seed availability in winter, restoring trees and tall grass and increasing vegetation diversity to maximize roadside conservation value.

Bioacoustic monitoring of New Zealand avifauna before and after aerial 1080 operations

<p>Introduced mammalian predators, namely possums, stoats and rats, are the leading cause of decline in native avifauna in New Zealand. The control of these species is essential to the persistence of native birds. A major component of mammal control in New Zealand is carried out through the aerial distribution of the toxin sodium monofluoroacetate (otherwise known as 1080). The use of this toxin, however, is subject to significant public debate. Many opponents of its use claim that forests will ‘fall silent’ following aerial operations, and that this is evidence of negative impacts on native bird communities. With the continued and likely increased use of this poison, monitoring the outcomes of such pest control operations is necessary to both address these concerns and inform conservation practice. The recent growth in autonomous recording units (ARUs) provides novel opportunities to conduct monitoring using bioacoustics. This thesis used bioacoustic techniques to monitor native bird species over three independent aerial 1080 operations in the Aorangi and Rimutaka Ranges of New Zealand. In Chapter 2, diurnal bird species were monitored for 10-12 weeks over two independent operations in treatment and non-treatment areas. At the community level, relative to non-treatment areas, the amount of birdsong recorded did not decrease significantly in treatment areas across either of the operations monitored. At the species level, one species, the introduced chaffinch (Fringilla coelebs), showed a significant decline in the prevalence of its calls in the treatment areas relative to non-treatment areas. This was observed over one of the two operations monitored. Collectively, these results suggest that diurnal native avifaunal communities do not ‘fall silent’ following aerial 1080 operations. The quantity of data produced by ARUs can demand labour-intensive manual analysis. Extracting data from recordings using automated detectors is a potential solution to this issue. The creation of such detectors, however, can be subjective, iterative, and time-consuming. In Chapter 3, a process for developing a parsimonious, template-based detector in an efficient, objective manner was developed. Applied to the creation of a detector for morepork (Ninox novaeseelandiae) calls, the method was highly successful as a directed means to achieve parsimony. An initial pool of 187 potential templates was reduced to 42 candidate templates. These were further refined to a 10-template detector capable of making 98.89% of the detections possible with all 42 templates in approximately a quarter of the processing time for the dataset tested. The detector developed had a high precision (0.939) and moderate sensitivity (0.399) with novel recordings, developed for the minimisation of false-positive errors in unsupervised monitoring of broad-scale population trends. In Chapter 4, this detector was applied to the short-term 10-12 week monitoring of morepork in treatment and non-treatment areas around three independent aerial 1080 operations; and to longer-term four year monitoring in two study areas, one receiving no 1080 treatment, and one receiving two 1080 treatments throughout monitoring. Morepork showed no significant difference in trends of calling prevalence across the three independent operations monitored. Longer-term, a significant quadratic effect of time since 1080 treatment was found, with calling prevalences predicted to increase for 3.5 years following treatment. Collectively, these results suggest a positive effect of aerial 1080 treatment on morepork populations in the lower North Island, and build on the small amount of existing literature regarding the short- and long-term response of this species to aerial 1080 operations.</p>

Bioacoustic monitoring of New Zealand avifauna before and after aerial 1080 operations

<p>Introduced mammalian predators, namely possums, stoats and rats, are the leading cause of decline in native avifauna in New Zealand. The control of these species is essential to the persistence of native birds. A major component of mammal control in New Zealand is carried out through the aerial distribution of the toxin sodium monofluoroacetate (otherwise known as 1080). The use of this toxin, however, is subject to significant public debate. Many opponents of its use claim that forests will ‘fall silent’ following aerial operations, and that this is evidence of negative impacts on native bird communities. With the continued and likely increased use of this poison, monitoring the outcomes of such pest control operations is necessary to both address these concerns and inform conservation practice. The recent growth in autonomous recording units (ARUs) provides novel opportunities to conduct monitoring using bioacoustics. This thesis used bioacoustic techniques to monitor native bird species over three independent aerial 1080 operations in the Aorangi and Rimutaka Ranges of New Zealand. In Chapter 2, diurnal bird species were monitored for 10-12 weeks over two independent operations in treatment and non-treatment areas. At the community level, relative to non-treatment areas, the amount of birdsong recorded did not decrease significantly in treatment areas across either of the operations monitored. At the species level, one species, the introduced chaffinch (Fringilla coelebs), showed a significant decline in the prevalence of its calls in the treatment areas relative to non-treatment areas. This was observed over one of the two operations monitored. Collectively, these results suggest that diurnal native avifaunal communities do not ‘fall silent’ following aerial 1080 operations. The quantity of data produced by ARUs can demand labour-intensive manual analysis. Extracting data from recordings using automated detectors is a potential solution to this issue. The creation of such detectors, however, can be subjective, iterative, and time-consuming. In Chapter 3, a process for developing a parsimonious, template-based detector in an efficient, objective manner was developed. Applied to the creation of a detector for morepork (Ninox novaeseelandiae) calls, the method was highly successful as a directed means to achieve parsimony. An initial pool of 187 potential templates was reduced to 42 candidate templates. These were further refined to a 10-template detector capable of making 98.89% of the detections possible with all 42 templates in approximately a quarter of the processing time for the dataset tested. The detector developed had a high precision (0.939) and moderate sensitivity (0.399) with novel recordings, developed for the minimisation of false-positive errors in unsupervised monitoring of broad-scale population trends. In Chapter 4, this detector was applied to the short-term 10-12 week monitoring of morepork in treatment and non-treatment areas around three independent aerial 1080 operations; and to longer-term four year monitoring in two study areas, one receiving no 1080 treatment, and one receiving two 1080 treatments throughout monitoring. Morepork showed no significant difference in trends of calling prevalence across the three independent operations monitored. Longer-term, a significant quadratic effect of time since 1080 treatment was found, with calling prevalences predicted to increase for 3.5 years following treatment. Collectively, these results suggest a positive effect of aerial 1080 treatment on morepork populations in the lower North Island, and build on the small amount of existing literature regarding the short- and long-term response of this species to aerial 1080 operations.</p>

Arcadia, The Museum Of Nature

<p>The loss of indigenous ancient forests has had a great impact to New Zealand habitats. Native birds, insects, fungi, plants and animals have been diminishing in diversity since human occupation. This is to a degree the result of intensive resource consumption and demand. Forestry, agriculture, mineral and gas resources were seen as more valuable than the ecosystems that existed before them. Our landscapes themselves became secondary. The particular infrastructure of open cast mining was chosen for this research. Mining represents a way to design active reclamation, while the mine site is still operating. Because of this, time becomes an integral component to the design process. The site is situated at Macraes flat, Otago. Ten kilometres of open cast mine, in operation since 1990. Open cast mining has produced great income. However, The cost of mining extends beyond an eyesore, it diminishes the quality of the land for any future use. Arcadia, the Museum of Nature is a vision of a place for preservation and for pride in ancestral property. A true “Arcadia” — a land of natural wonder. This is a museum of New Zealand’s key indigenous species. One designed through myth woven narratives, inspired by existing authors and generated through narrative experiments. To inspire, educate and showcase our unique ecologies, and endangered environments for future generations. Arcadia becomes a place to witness the succession of the natural world. A continuous time scale allows for a regenerative solution over years to centuries. Thereby showing the ability and resilience of nature in taking back from man’s intrusive tendencies. Rectifying the grotesque interruption of one of nature’s greatest tools, that of time. All the while harbouring our rare and unique wildlife. The museum of nature replaces the current system of remediation, and provides a more provocative solution to the end of modern day infrastructure.</p>

Arcadia, The Museum Of Nature

<p>The loss of indigenous ancient forests has had a great impact to New Zealand habitats. Native birds, insects, fungi, plants and animals have been diminishing in diversity since human occupation. This is to a degree the result of intensive resource consumption and demand. Forestry, agriculture, mineral and gas resources were seen as more valuable than the ecosystems that existed before them. Our landscapes themselves became secondary. The particular infrastructure of open cast mining was chosen for this research. Mining represents a way to design active reclamation, while the mine site is still operating. Because of this, time becomes an integral component to the design process. The site is situated at Macraes flat, Otago. Ten kilometres of open cast mine, in operation since 1990. Open cast mining has produced great income. However, The cost of mining extends beyond an eyesore, it diminishes the quality of the land for any future use. Arcadia, the Museum of Nature is a vision of a place for preservation and for pride in ancestral property. A true “Arcadia” — a land of natural wonder. This is a museum of New Zealand’s key indigenous species. One designed through myth woven narratives, inspired by existing authors and generated through narrative experiments. To inspire, educate and showcase our unique ecologies, and endangered environments for future generations. Arcadia becomes a place to witness the succession of the natural world. A continuous time scale allows for a regenerative solution over years to centuries. Thereby showing the ability and resilience of nature in taking back from man’s intrusive tendencies. Rectifying the grotesque interruption of one of nature’s greatest tools, that of time. All the while harbouring our rare and unique wildlife. The museum of nature replaces the current system of remediation, and provides a more provocative solution to the end of modern day infrastructure.</p>

Eradication of a highly invasive bird, the Common Myna Acridotheres tristis, facilitates the establishment of insurance populations of island endemic birds

Summary Common Myna Acridotheres tristis is considered to be among the world’s most damaging invasive species through disturbance, predation, competition pathogen introduction to native birds and other taxa. Claimed impacts on native birds have often been based on anecdotal reports. More substantive evidence of interference with small-island endemic birds has been reported, but impacts have rarely been quantified or subjected to experimental manipulation. On Denis Island (Seychelles), up to 10% of Seychelles Warblers Acrocephalus sechellensis, and small numbers of Seychelles Fodies Foudia sechellesis and Seychelles Paradise Flycatchers Terpsiphone corvina had head injuries following myna attacks, stimulating an eradication of the mynas. Populations of four species of Seychelles’ endemic birds, introduced to the island to establish insurance populations, were estimated before, during and after the completion of the eradication, permitting assessment of the impact of myna removal on populations of the endemics. Numbers of all four endemics increased following introduction, but increases in the numbers of Seychelles Magpie Robins Copsychus sechellensis and Seychelles Paradise Flycatchers accelerated after >90% of the mynas had been removed. All endemic populations continued to increase during and after completion of the eradication in 2015, and injuries to Seychelles Warblers, Seychelles Fodies, and Seychelles Paradise Flycatchers ceased. Habitat management within a designated conservation zone on the island, into which the endemics were released and subsequently spread to occupy most of the island, also contributed to the endemic birds’ global populations and to their improved conservation status. This study confirms that mynas negatively impact small island populations of endemic birds and suggests that their potential impact has been underestimated. Myna eradication should be considered vital before endangered endemic birds and other taxa susceptible to their negative impacts are translocated to small islands for conservation reasons.

Shakespeare’s Starlings

Scientists, environmentalists, and nature writers often report that all common starlings (Sturnus vulgaris) in North America descend from a flock released in New York City in 1890 by Eugene Schieffelin, a man obsessed with importing all the birds mentioned by Shakespeare. This article uses the methods of literary history to investigate this popular anecdote. Today starlings are much despised as an invasive species that displaces native birds and does almost a billion dollars worth of damage to agriculture annually. Because of the starling’s pest status, the Schieffelin story is considered a cautionary tale about the dangers of ecological ignorance. Diving into the history of the Schieffelin story reveals, however, that it is almost entirely fictional. Tracing how its elements emerged and changed over a century of retelling clarifies how the story came to shore up uncertainties in the bird’s environmental history and to distract from the lack of data supporting the starling’s supposedly disastrous impacts. In explaining how a fiction repeated over time attained the status of fact in debates about invasive species, this literary history suggests humanistic methods can serve as useful tools for understanding the value-laden narratives underpinning environmental attitudes and practices today.

A noteworthy case of rewilding Chinese yew from a garden population in eastern China

Chinese yew (Taxus wallichiana var. mairei) is ranked as a rare and endangered plant of first-grade protection of China. It has been widely cultivated in 17 provinces of China over the past few decades. However, little is known about the dispersion, rewilding, and ecological influence of Chinese yew’s offspring during cultivation. Here, we report a noteworthy case of this species, via ex situ conservation, which has successfully spread into different secondary forests, thus forming a stable regenerating population in eastern China. The establishment of this yew population, which has > 900 individuals and 7 ha area, can be ascribed to two key ecological factors: (1) secondary forest near the parent yews that provided suitable microhabitats in which progeny yews could germinate and grow, and (2) seed-foraging and transportation by native birds. Thus, this case may offer a pathway for conserving endangered Chinese Taxus species, which can attract frugivorous birds to disperse their seeds. In addition, it is necessary to monitor the growth performance of progeny population in the field.

Noisy Urbanization: Green Space Occupancy By Native Birds in a Mediterranean-Type South American City

Urban green spaces provide natural habitat for birds in city landscapes, yet the effects of noise and surrounding urban morphology on bird community structure and distribution are not well understood in Latin America, the second most urbanized region in the world. Santiago, Chile, located in the epicenter of the single portion of Mediterranean ecosystem in South America, is subject to extensive urbanization seen throughout Latin America. We examined the role of 65 urban green spaces (6 large: PAR and 59 small: SGS) in harboring native birds during winter 2019, analyzing the quality of green areas in terms of vegetation (i.e. NDVI, native vegetation, and tree cover), exotic bird species, noise levels, and surrounding urban matrix (i.e. building height and cover). Significantly higher noise levels were detected in SGS, along with significantly greater exotic bird (n=4) richness and abundance than PAR, which possessed significantly greater native bird (n=25) richness and abundance. Native birds were more abundant than exotic birds in green spaces with average noise levels < 52 dB and average NDVI > 0.5. Occupancy models indicate that green space occupancy by 50% of modeled native bird species was influenced by maximum noise levels, playing a larger role than vegetation (30%) and the urban matrix (0%). We stress the importance of developing networks of large green spaces in rapidly urbanizing regions, with abundant tree cover, surrounded by smaller urban morphology, and regulating noise levels to ensure the preservation of native bird communities in cities, particularly those of greater conservation value.