scholarly journals Comparing detectability patterns of bird species in small ponds using multi-method hierarchical modelling

2019 ◽  
Author(s):  
José M. Zamora-Marín ◽  
Antonio Zamora-López ◽  
José F. Calvo ◽  
Francisco J. Oliva-Paterna
Keyword(s):  
Sampling Methods ◽  
Bird Species ◽  
Breeding Period ◽  
Large Species ◽  
Imperfect Detection ◽  
Detection Rates ◽  
Hierarchical Modelling ◽  
Occupancy Detection ◽  
Animal Diversity ◽  
Conservation Actions

AbstractRobust knowledge of biodiversity distribution is essential for designing and developing effective conservation actions. However, monitoring programmes have historically assumed all species are detected equally with no spatial or temporal differences in their detection rates. However, recently, interest in accounting for imperfect detection has greatly increased in studies on animal diversity. In this respect, birds are the most widely used group for hierarchical occupancy-detection modelling, mainly due to the relative ease of sampling and the large number of bird datasets that are available. Nevertheless, there are no studies that have tried to evaluate the effectiveness of different bird sampling methods based on a hierarchical modelling approach. In an attempt to remedy this situation, we conducted point transects (PT), point transects plus video monitoring (PV) and mist netting (MN) in 19 small ponds located in the province of Murcia, southeastern Spain, one of the most arid regions of Europe. Multi-method hierarchical models were fitted to the detection histories of 36 common bird species with three main objectives: to compare the effectiveness of the three sampling methods for detecting the bird species using ponds, to assess the effect of sampling date on species detectability, and to establish the influence of body size and diet on species detectability. The results showed PV to be the most effective sampling method for detecting species occupancy, although detection rates ranged widely among bird groups, and some large species were weakly detected by all the methods. Average detectability increased during the breeding period, a pattern shown similarly by all sampling methods. Our approach is particularly applicable to both single- and multi-species bird monitoring programmes. We recommend evaluating the cost-effectiveness of available methods for sampling design in order to reduce costs and improve effectiveness.

scholarly journals Comparing detectability patterns of bird species using multi-method occupancy modelling

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
José M. Zamora-Marín ◽  
Antonio Zamora-López ◽  
José F. Calvo ◽  
Francisco J. Oliva-Paterna
Keyword(s):  
Direct Observation ◽  
Bird Species ◽  
Breeding Period ◽  
Accurate Information ◽  
Large Species ◽  
Occupancy Models ◽  
Occupancy Modelling ◽  
Detection Rates ◽  
Bird Monitoring ◽  
Conservation Actions

AbstractA robust knowledge of biodiversity distribution is essential for designing and developing effective conservation actions. The choice of a suitable sampling method is key to obtaining sufficiently accurate information of species distribution and consequently to improve biodiversity conservation. This study applies multi-method occupancy models to 36 common bird species associated with small ponds in the province of Murcia (south-eastern Spain), one of the most arid regions of Europe, in order to compare their effectiveness for detecting different bird species: direct observation, combined observation and video monitoring and mist netting captures. The results showed that the combined method and direct observation were similar and most effective than mist netting for detecting species occupancy, although detection rates ranged widely among bird groups, while some large species were poorly detected by all the methods used. Average detectability did not increase during the breeding period. The chosen approach is particularly applicable to both single- and multi-species bird monitoring programmes. However, we recommend evaluating the cost-effectiveness of all the available methods in order to reduce costs and improve the success of sampling designs.

scholarly journals Detection Rate of Bird Species and What It Depends on: Tips for Field Surveys

2022 ◽  
Vol 9 ◽  
Author(s):  
Federico Morelli ◽  
Vojtěch Brlík ◽  
Yanina Benedetti ◽  
Raphaël Bussière ◽  
Lucie Moudrá ◽  
...  
Keyword(s):  
Body Mass ◽  
Detection Rate ◽  
Bird Species ◽  
Imperfect Detection ◽  
Detection Rates ◽  
Field Surveys ◽  
Species Detection ◽  
Total Species Richness ◽  
Number Of Individuals ◽  
Total Species

Bird counting inevitably suffers from imperfect detection, which varies across species, habitats, period of the day, and seasons. Although various modeling techniques have recently been developed to account for this phenomenon, the biological basis of natural variation in detection remains insufficiently known. This study examined the bird species’ detection rate throughout the day, considering their body mass and diet type, concerning the environment and weather characteristics. Species detection rates were significantly affected by the number of individuals of that species but were unrelated to body mass. Overall, species with the highest detection rate were Corn bunting, Blackbird, European robin, House sparrow and Common chiffchaff. Granivores-insectivores and insectivores showed significant differences in detection rates throughout the day among habitats, with higher detection rates in grasslands during the afternoon. Insectivores showed higher detection rates in farmland during midday (warmest time of the day). Granivores, omnivores and scavengers did not show changes in detection rates in different day periods. Such patterns in daily detection rates were significant even when considering abundance and total species richness in each community. Finally, cloudiness was unrelated to the overall detection rate of birds, while temperature and wind affected detection rates in some guilds. Our findings provide some advice for choosing a suitable ornithological sampling method by considering the avian communities composition in combination with the type of environment, the diet of bird species, and the period of the day.

scholarly journals Female song in the Cyprus Wheatear Oenanthe cypriaca

2021 ◽  
Author(s):  
Robert Patchett ◽  
Alexander N. G. Kirschel ◽  
Joanna Robins King ◽  
Patrick Styles ◽  
Will Cresswell
Keyword(s):  
Breeding Season ◽  
Bird Species ◽  
Breeding Period ◽  
Territorial Defence ◽  
Multiple Functions ◽  
Male Song ◽  
Female Song ◽  
Mate Acquisition

AbstractFemale song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition.

scholarly journals Changes in surface water drive the movements of Shoebills

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marta Acácio ◽  
Ralf H. E. Mullers ◽  
Aldina M. A. Franco ◽  
Frank J. Willems ◽  
Arjun Amar
Keyword(s):  
Surface Water ◽  
Optimal Foraging ◽  
Animal Movement ◽  
Bird Species ◽  
Individual Variability ◽  
Home Ranges ◽  
Age Classes ◽  
Water Index ◽  
Normalized Difference Water Index ◽  
Conservation Actions

AbstractAnimal movement is mainly determined by spatial and temporal changes in resource availability. For wetland specialists, the seasonal availability of surface water may be a major determinant of their movement patterns. This study is the first to examine the movements of Shoebills (Balaeniceps rex), an iconic and vulnerable bird species. Using GPS transmitters deployed on six immature and one adult Shoebills over a 5-year period, during which four immatures matured into adults, we analyse their home ranges and distances moved in the Bangweulu Wetlands, Zambia. We relate their movements at the start of the rainy season (October to December) to changes in Normalized Difference Water Index (NDWI), a proxy for surface water. We show that Shoebills stay in the Bangweulu Wetlands all year round, moving less than 3 km per day on 81% of days. However, average annual home ranges were large, with high individual variability, but were similar between age classes. Immature and adult Shoebills responded differently to changes in surface water; sites that adults abandoned became drier, while sites abandoned by immatures became wetter. However, there were no differences in NDWI of areas used by Shoebills before abandonment and newly selected sites, suggesting that Shoebills select areas with similar surface water. We hypothesise that the different responses to changes in surface water by immature and adult Shoebills are related to age-specific optimal foraging conditions and fishing techniques. Our study highlights the need to understand the movements of Shoebills throughout their life cycle to design successful conservation actions for this emblematic, yet poorly known, species.

scholarly journals How many bird extinctions have we prevented?

Oryx ◽  
2006 ◽  
Vol 40 (3) ◽  
pp. 266-278 ◽  
Author(s):  
Stuart H.M. Butchart ◽  
Alison J. Stattersfield ◽  
Nigel J. Collar
Keyword(s):  
Invasive Species ◽  
Captive Breeding ◽  
Extinction Risk ◽  
Bird Species ◽  
Iucn Red List ◽  
Additional Species ◽  
Conservation Actions ◽  
Declining Populations ◽  
Population Sizes ◽  
Principal Actions

Considerable resources and efforts have been directed at biodiversity conservation in recent years, but measures of the success of conservation programmes have been limited. Based on information on population sizes, trends, threatening processes and the nature and intensity of conservation actions implemented during 1994–2004, we assessed that 16 bird species would have probably become extinct during this period if conservation programmes for them had not been undertaken. The mean minimum population size of these 16 species increased from 34 to 147 breeding individuals during 1994–2004. In 1994, 63% of them had declining populations but by 2004, 81% were increasing. Most of these species (63%) are found on islands. The principal threats that led to their decline were habitat loss and degradation (88%), invasive species (50%) and exploitation (38%), a pattern similar to that for other threatened species, but with exploitation and invasive species being relatively more important. The principal actions carried out were habitat protection and management (75% of species), control of invasive species (50%), and captive breeding and release (33%). The 16 species represent only 8.9% of those currently classified as Critically Endangered, and 1.3% of those threatened with extinction. Many of these additional species slipped closer to extinction during 1994–2004, including 164 that deteriorated in status sufficiently to be uplisted to higher categories of extinction risk on the IUCN Red List (IUCN, 2006). Efforts need to be considerably scaled up to prevent many more extinctions in the coming decades. The knowledge and tools to achieve this are available, but we need to mobilize the resources and political will to apply them.

scholarly journals Rise-Up mist-netting (RUM): a mobile protocol for trapping wary territorial birds

2021 ◽  
Vol 61 ◽  
pp. e20216110
Author(s):  
Paulo Sérgio Amorim ◽  
Mariana Fonseca Rossi ◽  
André de Camargo Guaraldo
Keyword(s):  
Urban Area ◽  
Rural Areas ◽  
Urban Areas ◽  
General Public ◽  
Bird Species ◽  
Breeding Period ◽  
The Novel ◽  
Limited Space ◽  
Trapping Methods ◽  
Visual Impacts

Many bird species avoid traditional traps such as mist nets, thus alternative trapping methods are often needed. The Rufous Hornero (Furnariidae: Furnarius rufus) is one such species that was captured so far using conventional mist netting in rural areas or using nest-targeted traps, which risk nest damage and abandonment. Here we describe the novel rise-up mist-netting (RUM) protocol and its catchability for the wary and territorial Rufous Hornero in an urban area. The RUM trap allowed us quickly capturing 40 Rufous Hornero individuals even in paved parking lots and streets during the bird’s breeding period. The RUM is an active and targeted protocol that demands a single and quickly trainable field assistant. Therefore, it should also enable the capture of many understudied territorial but wary species. Moreover, it has enough mobility to fit studies in urban areas, and whenever researchers may deal with limited space and, at the same time, should reduce negative visual impacts to the general public of birds’ capturing and banding procedures.

scholarly journals Language barriers in global bird conservation

2021 ◽  
Author(s):  
Pablo Jose Negret ◽  
Scott Consaul Atkinson ◽  
Bradley Woodworth ◽  
Marina Corella Tor ◽  
James Allan ◽  
...  
Keyword(s):  
Scientific Information ◽  
Bird Species ◽  
Language Barriers ◽  
Language Diversity ◽  
Bird Conservation ◽  
Western Asia ◽  
Conservation Actions ◽  
Official Languages ◽  
Multiple Languages ◽  
Effective Conservation

Multiple languages being spoken within a species distribution can impede communication among conservation stakeholders, the compilation of scientific information, and the development of effective conservation actions. Here, we investigate the number of official languages spoken within the distributions of 10,863 bird species to identify which ones might be particularly affected by consequences of language barriers. We show that 1587 species have 10 languages or more spoken within their distributions. Threatened, migratory and wide-ranging species have especially many languages spoken within their distribution. Particularly high numbers of species with many languages within their distribution are found in Eastern Europe, Russia and central and western Asia. Global conservation efforts would benefit from implementing guidelines to overcome language barriers, especially in regions with high species and language diversity.

scholarly journals Brasilia tapaculo (Scytalopus novacapitalis) seasonality and site occupancy in altitudinal riparian environments after non-natural burnings and feral pig invasion in Serra da Canastra National Park, Brazil

2020 ◽  
Author(s):  
I. L. D. Cunha ◽  
M. G. Reis ◽  
C. Z. Fieker ◽  
M. M. Dias
Keyword(s):  
National Park ◽  
Bird Species ◽  
Site Occupancy ◽  
Early Spring ◽  
Control Area ◽  
Southeastern Brazil ◽  
Breeding Period ◽  
Feral Pigs ◽  
Management Actions ◽  
Gallery Forests

Abstract The Brasilia Tapaculo, Scytalopus novacapitalis Sick, 1958, is a rare, geographically restricted, and endangered bird species that inhabits riparian vegetation of Cerrado, mainly Gallery Forests. In Serra da Canastra National Park, southeastern Brazil, wetlands are under threat due to frequent non-natural burnings and invasion by feral pigs, Sus scrofa, Linnaeus, 1758. We aimed to evaluate the possible effects of seasonal variations on S. novacapitalis records in undisturbed habitats and answer questions about how fire and feral pigs may affect site occupancy of the species. Transects alongside riparian environments were used to survey n=21 sites, totalizing 7.5 Km, from 2014 to 2019. Results indicated the season influenced both, spontaneous records and induced encounters by playback method, which were more abundant in breeding period, from early spring to summer. The use of playback significantly increased the amount of records in all seasons. The probability of site occupancy in all studied area was higher in late spring (ψ=0.91) and lower in autumn (ψ=0.73). In burned sites (n=8), the first post-fire month showed the lowest probability of occupancy, but there was a rapid recovery in 2nd month and stabilization similar to control area from the 3rd month ahead. After sites (n=11) were invaded by feral pigs, the estimation of site occupancy indicated a slight drop in first two months, but after the 3rd month of invasion the decreasing pattern enhanced the discrepancy with undisturbed areas. It is important to keep monitoring S. novacapitalis population and their threats, to subsidize management actions, especially to avoid frequently unusual burnings in riparian forests, and to block the access of feral pigs to wetlands.

scholarly journals Ornithocenosis Structure in Fresh and Wet Sudubravas of Kyiv Polissya during the Breeding Period

2016 ◽  
Vol 50 (3) ◽  
pp. 241-250
Author(s):  
A. V. Plyha
Keyword(s):  
Population Density ◽  
Age Groups ◽  
Bird Species ◽  
Pine Forests ◽  
Breeding Period ◽  
Ecological Group ◽  
Ecological Groups ◽  
Age Group ◽  
Majority Population ◽  
Species Lists

Abstract This research was carried out in Kyiv Polissya geobotanical province, in one of most common woods type - fresh and wet sudubravas. Its purpose is to determine ornithocenosis structure in different age groups of this type of forest. To achieve that, forest bird species lists were composed, their population density and that of ecological groups of birds were calculated. In the course of the research in the breeding periods of 2013-2014, two-time surveys were carried out on 12 survey routes of total length 33 km. For further analysis, forests were divided into age groups: 0-20 years, 20-40 years, 40-60 years, 60-80 years, 80-100 years and forests over 100 years. Altogether 53 bird species were found. Species lists were poorest in the forests of 0-20 years (18 species), and richest in the forests over 100 years (39 species). Minimal population density was 473 individuals per square kilometer in the youngest forest age group of 0-20 years, maximal - 2155 individuals per square kilometer in pine forests aged over 100 years. Analysis of different population densities of ecological groups reveals steadily growing numbers of hollow-nesting birds and tree-nesting birds in accordance with aging of the forests. In older forests hollow-nesting birds constitute an absolute majority. Population density of another ecological group shows no such direct tendency.

scholarly journals Migratory connectivity in the context of differential migration

2018 ◽  
Vol 14 (12) ◽  
pp. 20180679 ◽  
Author(s):  
Martins Briedis ◽  
Silke Bauer
Keyword(s):  
Population Dynamics ◽  
Differential Mortality ◽  
Breeding Period ◽  
Migratory Connectivity ◽  
Differential Migration ◽  
Relative Contribution ◽  
Breeding Populations ◽  
Conservation Actions ◽  
Carry Over ◽  
The Times

Understanding how breeding populations are spatially and temporarily associated with one another over the annual cycle has important implications for population dynamics. Migratory connectivity typically assumes that populations mix randomly; yet, in many species and populations, sex-, age- or other subgroups migrate separately, and/or spend the non-breeding period separated from each other—a phenomenon coined differential migration. These subgroups likely experience varying environmental conditions, which may carry-over to affect body condition, reproductive success and survival. We argue that environmental or habitat changes can have disproportional effects on a population's demographic rates under differential migration compared to random mixing. Depending on the relative contribution of each of these subgroups to population growth, environmental perturbations may be buffered (under-proportional) or amplified (over-proportional). Thus, differential migration may result in differential mortality and carry-over effects that can have concomitant consequences for dynamics and resilience of the populations. Recognizing the role of differential migration in migratory connectivity and its consequences on population dynamics can assist in developing conservation actions that are tailored to the most influential demographic group(s) and the times and places where they are at peril.

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