Site-Use Intensity, Cultural Modification of the Environment, and the Development of Agricultural Communities in Southern Arizona

2005 ◽  
Vol 70 (3) ◽  
pp. 403-431 ◽  
Author(s):  
Rebecca M. Dean
Keyword(s):  
Human Impacts ◽  
Bird Species ◽  
Food Sources ◽  
Ecological Niches ◽  
Agricultural Communities ◽  
Local Environments ◽  
Middle Archaic ◽  
Site Use ◽  
Transition To Agriculture ◽  
Cultural Modification

Some non-prey animals, including certain rodent and bird species, are particularly good indicators of local environments, and are argued to provide an alternative way to look at the emergence of sedentism before, during, and after the transition to agriculture. With the first villages and irrigated fields, human impacts on the environment opened new ecological niches and affected the composition of local pest populations. Some of these animals would have been attracted to the new food sources available in village environments, while others may have been driven away by the destruction of their habitat. In southern Arizona, changes in archaeological pest assemblages are a source of information on the degree of site-use intensity prehistorically and how it changed through the Archaic and Hohokam cultural sequence. Faunal data from the Hohokam region suggest that the earliest farmers in the region were not significantly more sedentary than their Middle Archaic predecessors, and indeed site-use intensity did not increase substantially until well after the introduction of domestic plants.

scholarly journals Breeding biology and post-fledging dispersal of red-crowned parakeets (Cyanoramphus novaezelandiae) translocated to a fenced mainland sanctuary

2021 ◽  
Author(s):  
◽  
Ellen Irwin
Keyword(s):  
Reproductive Success ◽  
Human Impacts ◽  
Release Site ◽  
Habitat Destruction ◽  
Breeding Biology ◽  
Food Sources ◽  
Lifetime Reproductive Success ◽  
Species Dispersal ◽  
Dispersal Patterns ◽  
Mammalian Predators

<p>With human impacts like habitat destruction and climate change contributing to range contractions in species, translocations stand out as an important tool for conserving species suffering from these effects. However, an understanding of the life history of many threatened species prior to translocation is often lacking, but critical for translocation success. For example, dispersal away from the release site—particularly when a protected release site is surrounded by unmanaged habitat—can result in translocation failure, and therefore successful translocation practice must include an understanding of a species’ dispersal patterns. I conducted a study examining the breeding biology and post-fledging dispersal of a population of red-crowned parakeets Cyanoramphus novaezelandiae), or kakariki, recently translocated to a mainland sanctuary in Wellington, New Zealand. The sanctuary, ZEALANDIA, is fenced to exclude invasive mammalian predators; however, birds can and do leave. Approximately one-third of juveniles that dispersed outside the sanctuary were killed by predators. Kakariki post-fledging dispersal was male-biased, possibly driven by inbreeding avoidance, and distance dispersed decreased with increasing body condition. Parental age may have also influenced offspring dispersal. In addition, I found that kakariki reproductive success may be affected by age, and estimated lifetime reproductive success was >30 fledglings by age five. Conservation initiatives could work on controlling predators in currently unprotected reserves and around food sources that kakariki targeted, particularly in summer and autumn when many plants are fruiting and recently fledged juveniles are more active. Future translocations should consider selecting younger birds to translocate to take advantage of their high lifetime reproductive success and therefore improve viability of populations.</p>

scholarly journals Spatial and temporal patterns of bird species diversity in the Pantanal of Mato Grosso, Brazil: implications for conservation

2006 ◽  
Vol 66 (2a) ◽  
pp. 393-404 ◽  
Author(s):  
J. E. C. Figueira ◽  
R. Cintra ◽  
L. R. Viana ◽  
C. Yamashita
Keyword(s):  
Human Impacts ◽  
Bird Species ◽  
Bird Community ◽  
The Other ◽  
Resident Species ◽  
Spatial And Temporal Patterns ◽  
Mato Grosso ◽  
Bird Survey ◽  
Bird Species Diversity ◽  
Habitat Generalists

Analysis of a three-year bird survey in the pantanal of Poconé revealed that most of the resident and seasonal birds are habitat generalists, using two or more habitats. In this study, previously sampled habitats were ranked in relation to species richness and stability (as measured by the ratio of seasonal to resident species). In all, nine habitats were grouped into three categories; results are as follows: 1) forests: more species-rich and more stable; 2) cerrado: intermediate levels; and 3) aquatic: less species-rich and less stable. The number of seasonal species remained relatively constant in forests throughout the year, while increasing in the other habitats during the dry season. The abundance of resident species seems to be related to species use of multiple habitats. Although many species were found to be habitat generalists, we discuss possible consequences of habitat loss and other human impacts on efforts to conserve this important bird community.

scholarly journals Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction

2020 ◽  
Vol 117 (24) ◽  
pp. 13596-13602 ◽  
Author(s):  
Gerardo Ceballos ◽  
Paul R. Ehrlich ◽  
Peter H. Raven
Keyword(s):  
Ecosystem Services ◽  
Endangered Species ◽  
Mass Extinction ◽  
Life Support ◽  
Human Impacts ◽  
Bird Species ◽  
Wildlife Trade ◽  
Ecological Interactions ◽  
Terrestrial Vertebrates ◽  
Sixth Mass Extinction

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second, the distribution of those species highly coincides with hundreds of other endangered species, surviving in regions with high human impacts, suggesting ongoing regional biodiversity collapses. Third, close ecological interactions of species on the brink tend to move other species toward annihilation when they disappear—extinction breeds extinctions. Finally, human pressures on the biosphere are growing rapidly, and a recent example is the current coronavirus disease 2019 (Covid-19) pandemic, linked to wildlife trade. Our results reemphasize the extreme urgency of taking much-expanded worldwide actions to save wild species and humanity’s crucial life-support systems from this existential threat.

scholarly journals Anti-predator behavior along elevational and latitudinal gradients in dark-eyed juncos

2019 ◽  
Vol 66 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Madelin Andrade ◽  
Daniel T Blumstein
Keyword(s):  
Human Impacts ◽  
Bird Species ◽  
Passerine Bird ◽  
Latitudinal Gradients ◽  
Junco Hyemalis ◽  
Predator Density ◽  
Elevational Gradients ◽  
Main Driver ◽  
Flight Initiation ◽  
Predator Behavior

Abstract Flight-initiation distance (FID), the distance between an individual and experimenter when it begins to flee, can be used to quantify risk-assessment. Among other factors, prior studies have shown that latitude explains significant variation in avian FID: at lower latitudes, individuals and species have longer FIDs than those living at higher latitudes. No prior studies have focused on the effect of elevation on FID. Given the similar patterns of seasonality, climate, and potentially predator density, that covary between latitude and elevation, birds at higher elevations might tolerate closer approaches. We asked whether elevation or latitude would explain more variation in the FID of a common passerine bird species, dark-eyed juncos (Junco hyemalis). Juncos live in a variety of habitats along both latitudinal and elevational gradients. We found that statistical models containing elevation as a variable explained more of the variation in FID than did models containing latitude. We also found, unexpectedly, that birds at higher elevation fled at greater distances. While more predators were sighted per hour at higher elevations than at lower elevations, the frequency of predator sightings did not explain a significant amount of variation in FID. This result questions whether predator density is the main driver of risk perception along elevational gradients. Nonetheless, because elevation explains more variation in FID than latitude in at least one species, these findings have direct implications on how human impacts on birds are managed. Specifically, those designing set-back zones to reduce human impact on birds may consider modifying them based on both latitude and elevation.

scholarly journals Slave to the Tides: Spatiotemporal Foraging Dynamics of Spring Staging Black Brant

The Condor ◽  
2006 ◽  
Vol 108 (3) ◽  
pp. 661-677 ◽  
Author(s):  
Jeffrey E. Moore ◽  
Jeffrey M. Black
Keyword(s):  
Seasonal Changes ◽  
Negative Binomial ◽  
Bird Species ◽  
Negative Binomial Regression ◽  
Nutrient Content ◽  
Latitudinal Gradients ◽  
Tidal Channels ◽  
Branta Bernicla ◽  
Black Brant ◽  
Site Use

AbstractArctic-nesting geese depend on nutrients acquired during spring migration for reproduction, and thus should attempt to maximize nutrient intake while on staging areas. We investigated site use of Black Brant (Branta bernicla nigricans) at an important staging location—Humboldt Bay, California—to determine whether birds selected the most profitable feeding areas available. Migrating Brant feed almost exclusively on eelgrass (Zostera marina), which is restricted in availability due to daily and seasonal tidal cycles. We mapped foraging Brant locations during low tides and collected eelgrass samples to describe food resources in 31 areas in the bay. We used negative binomial regression to evaluate goose densities during different tidal levels and times of season as a function of food biomass and nutrient content, distance from grit sites, and substrate elevation. Results varied by time of season and tidal depth, but Brant densities were positively correlated with eelgrass protein, calcium, and biomass in most analyses. Brant usually fed in the deepest possible areas permitted by tides, and closer to tidal channels, where biomass and nutrient content of eelgrass were greater and where depletion from grazing was probably less. During higher low tides, Brant fed closer to previously visited grit sites. Tide cycles change over the course of the Brant's staging period on the bay, enabling longer and more frequent access to deeper eelgrass meadows as spring progresses. These seasonal changes in tidal pattern coincide with seasonal changes in Brant use of the bay. Thus, migration patterns for estuarine bird species might be shaped by latitudinal gradients in both food phenology and seasonal tidal patterns.

scholarly journals Mangrove bird community of Paranaguá Bay - Paraná, Brazil

2007 ◽  
Vol 50 (1) ◽  
pp. 75-83 ◽  
Author(s):  
Luiz Augusto Macedo Mestre ◽  
Ricardo Krul ◽  
Valéria dos Santos Moraes
Keyword(s):  
Human Impacts ◽  
Bird Species ◽  
Passer Domesticus ◽  
Bird Community ◽  
Abundant Species ◽  
Marine Conservation ◽  
Point Counts ◽  
Flying Insects ◽  
Paranaguá Bay ◽  
Conservation Plans

This study describes the mangrove bird community of Paranaguá Bay in Paraná - South Brazil. Seasonal surveys were conducted during September 1997 to September 1998 at three sites in Paranaguá Bay. Frequencies and abundances of birds were registered in 200m transects and one hour point counts. A total of 81 bird species were observed in the three sampling sites. Most of the bird species in Paranaguá mangroves are fruits, seeds and arthropods consumers, and predators of flying insects. The most frequent and abundant species were Egretta caerulea, Ceryle torquata, Chloroceryle amazona, Pitangus sulphuratus, Turdus amaurochalinus and Parula pitiayumi. The bird community of these three sites is composed mainly by forest bird species. The mangroves of Paranaguá Bay shelter one of the richest avifauna of Brazilian mangroves. Differences between sampling sites could be related to the proximity of the Paranaguá city and human impacts in the areas. Only in the most disturbed site were observed Passer domesticus and large flocks of Coragyps atratus. This study contributed to the knowledge of mangrove communities, and could be an important basis to fluvial-marine conservation plans in Paraná- Brazil.

scholarly journals Different definitions of species presence to refine estimates of local species richness

2017 ◽  
Author(s):  
Alejandro Ruete ◽  
Tomas Pärt ◽  
Åke Berg ◽  
Jonas Knape ◽  
Debora Arlt
Keyword(s):  
Species Richness ◽  
Breeding Season ◽  
Temporal Resolution ◽  
Explanatory Power ◽  
Bird Species ◽  
High Temporal Resolution ◽  
Occupancy Models ◽  
Local Species Richness ◽  
Site Use ◽  
Local Species

Abstract Aim To improve predictions of spatial and temporal patterns of species richness it is important to consider how species presence at a site is defined. This is because this definition affects our estimate of species richness, which should be aligned with the aims of the study, e.g. estimating richness of the breeding community. Here we explore the sensitivity of species richness estimates to criteria for defining presence of species (e.g. in relation to number of days present during the breeding season) at 107 wetlands. Innovation We use opportunistic citizen science data of high density (a total of 151,817 observations of 77 wetland bird species; i.e. about 16 observations per day) to build site-occupancy models calculating occupancy probabilities at a high temporal resolution (e.g. daily occupancies) to derive probabilistic estimates of seasonal site use of each species. We introduce a new way for defining species presence by using different criteria related to the number of days the species are required to be present at local sites. We compared patterns of species richness when using these different criteria of species inclusions. Main conclusion While estimates of local species richness derived from high temporal resolution occupancy models are robust to observational bias, these estimates are sensitive to restrictions concerning the number of days of presence required during the breeding season. Unlike complete local species lists, summaries of seasonal site use and different presence criteria allow identifying differences between sites and amplifying the variability in species richness among sites. Thus, this approach allows filtering out species according to their phenology and migration behaviour (e.g. passer-by species) and could improve the explanatory power of environmental variables on predictive models.

scholarly journals Avifauna of the upper Purus River: relevant records for an area lacking ornithological surveys

2021 ◽  
Vol 61 ◽  
pp. e20216121
Author(s):  
Fernando Igor de Godoy ◽  
Edson Guilherme ◽  
Diego Pedroza ◽  
Ricardo Antônio de Andrade Plácido
Keyword(s):  
Tropical Forest ◽  
Amazon Basin ◽  
Bird Species ◽  
Field Trips ◽  
The State ◽  
Knowledge Gaps ◽  
Number Of Species ◽  
Local Environments ◽  
The World ◽  
High Diversity

Birds are the best-known vertebrate group, although many localities in the world are considered to be knowledge gaps. This is the case of many little-known environments in the Amazon biome, the world’s largest tropical forest. Here, we present a survey of birds in the upper Purus basin, comprising the municipalities of Manoel Urbano and Feijó in the Brazilian state of Acre, and Boca do Acre and Pauini in the state of Amazonas. In this region, poorly-studied habitats, such as open rainforest dominated by palms or bamboo, still predominate. We recorded 452 bird species during 45 field trips between May and July in 2016, and June to August in 2017. Twenty-four of these species are associated with bamboo habitat, 28 are endemic to the southwestern Amazon basin, and seven are threatened with extinction. This high diversity is typical of the western Amazon basin, one of the richest regions in the world in the number of species, due to the heterogeneity of the local environments. The data presented here highlight the importance of the region for the conservation of birds, including species typical of the western Amazon, some of which are still poorly-known.

scholarly journals Dietary composition of birds species at an inland airport in South Africa

2002 ◽  
Vol 21 (1) ◽  
pp. 16-18
Author(s):  
A. C. Kok ◽  
O. B. Kok
Keyword(s):  
Bird Species ◽  
Stomach Contents ◽  
Total Sample ◽  
Dry Mass ◽  
Food Sources ◽  
Mass Composition ◽  
Potential Threat ◽  
Important Prey ◽  
Lesser Kestrel ◽  
Main Food Source

Stomach contents of 51 bird species that posed a potential threat to aviation were collected at the Bloemfontein airport over a period of 11 years (1985-1995). Numerically the crowned plover (Vanellus coronatus), and the lesser kestrel (Falco naumanni), blacksmith plover (V. armatus), whitewinged korhaan (Eupodotis afraoides), doublebanded courser (Smutsornis africanus), spotted dikkop (Burhinus capensis), cattle egret (Bubulcus ibis), Swainson’s francolin (Francolinus swainsonii) and Orange River francolin (F. levaillantoides) in sequence of importance, constituted 91,0% of the total sample (3 544). In general insects can be considered the main food source of the birds concerned. Based on dry mass composition the Isoptera, followed by the Coleoptera and Orthoptera, constituted the most important component in the diet. The Isoptera, more specifically the harvester termite (Hodotermes mossambicus), is, moreover, the only important prey taxon showing a conspicuous utilisation peak during the relative food shortage of the dry season. Evidently, temporary superabundant food sources that periodically come about in grassland habitats are opportunistically utilised by the birds.

Micro-habitats Utilizations, Feeding Niche Overlapping, and Management Systems Impacts on Community Tolerances of Wasp Species within Oil Palm Plantations.

2016 ◽  
Vol 6 (1) ◽  
pp. 888-904
Author(s):  
Ahmad Bukhary, A.K. ◽  
M. Y. Ruslan
Keyword(s):  
Oil Palm ◽  
Food Sources ◽  
Management Systems ◽  
Ecological Niches ◽  
Similar Species ◽  
Habitat Types ◽  
Wasp Species ◽  
Feeding Niche ◽  
Hymenopteran Species ◽  
Species Groups

A study on micro-habitats utilizations, feeding niche overlapping, and management systems impacts pertaining to hymenopteran community were evaluated at five chosen oil palm age stands within FELDA Sungai Tekam oil palm plantations, Pahang.  Samplings were done within the duration of one year, employing the standard Malaise traps, starting from February 2013 till February 2014, involving both hot and wet seasons. 60 species, from 17 families and 35 subfamilies were successfully collected during the sampling periods. Eight defined micro-habitats were elaborated, with the subdivisions of major, minor, stable, and risky micro-habitat types. Management systems impacts were associated with the applications of chemical herbicides and fertilizers. Species groups were formed using Two-Way Hierarchical Cluster Dendrogram, following 75% of information remaining. Three species groups were formed for hot and wet seasons respectively, with the first group involved nearly half of the overall hymenopteran community. Beneficial nectariferous plants, heaps of chipped rotting oil palm trunks, and remnants of rotting forest logs were all the prominent micro-habitats associated will all cases of hymenopteran species groups, for both cases of major and minor micro-habitat types. Application of BASTA, Glyphosate-Type-A and Type-B herbicides, as well as NK-Mix, Borax, and GML chemical fertilizers were all highly correlated with hymenopteran species groups, showing the high tolerance of most hymenopteran species towards the employed management systems, with reference to minor micro-habitats. Strong feeding ecological niches and plexus values between species of similar species groups formed were specifically associated with discrete but connected minor micro-habitats with weaker food chains, collectively forming larger stable food webs within major micro-habitats. Suggestions on maintaining minor micro-habitats for the survival of most hymenopteran community, as well as the sustenance of their food sources were also discussed. 

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