scholarly journals Biometrics as a determinant of the origins of seabirds killed in oil spills and other incidents

2008 ◽  
Vol 18 (3) ◽  
pp. 229-241 ◽  
Author(s):  
Robert T. Barrett ◽  
Tycho Anker-Nilssen ◽  
Vidar Bakken ◽  
Hallvard Strøm ◽  
Yuri Krasnov ◽  
...  
Keyword(s):  
Breeding Season ◽  
Oil Spills ◽  
Russian Population ◽  
Systematic Variation ◽  
Critically Endangered ◽  
Body Measurements ◽  
Reasonable Accuracy ◽  
Norwegian Population ◽  
Brunnich’S Guillemot ◽  
Made In

AbstractCommon Guillemots Uria aalge and Brünnich's Guillemots U. lomvia are common victims of oil spills, drowning in fishing nets and winter wrecks. Because the Norwegian population of Common Guillemots is classified as critically endangered and the Russian population of the Brünnich's Guillemot has declined greatly, it is important to be able to identify the origins of birds killed outside the breeding season. Measurements of birds made in nine colonies in the Barents and Norwegian Seas showed that although it is impossible to determine with reasonable accuracy the colony of origin from body measurements, the most likely sea of origin of Common Guillemots may be determined on the basis of wing and head + bill lengths, whereas there was no systematic variation in any measurement of Brünnich's Guillemots.

Reproductive Biology and Development of the Water Rat, Hydromys chrysogaster, in Captivity

1982 ◽  
Vol 9 (1) ◽  
pp. 39 ◽  
Author(s):  
PD Olsen
Keyword(s):  
Breeding Season ◽  
Developmental Stages ◽  
Post Partum ◽  
Growth Curves ◽  
Gestation Length ◽  
Body Measurements ◽  
Sperm Production ◽  
Crown Rump Length ◽  
Rate Of Increase ◽  
Hydromys Chrysogaster

In a captive colony of H. chrysogaster most litters were born between September and March, although some were born in every month except June. Most females had regular oestrous cycles in the breeding season but there were isolated instances of oestrus in every month. In mature males, testes were scrota1 and there was full sperm production all year. There was some regression in weight of male accessory reproductive glands in the autumn and winter. Oestrus lasted 10 days (range 7-17), and its stages: pro-oestrus 1 day, oestrus 2 days, metoestrus 2 days, anoestrus 5 days. Some instances of delayed implantation were suspected. Gestation length was 34 days (33-41). Parturition was followed the next day by a postpartum oestrus, lasting 1 day. Lactation anoestrus was at least 3 weeks. Litter size was 3.29 � 1.26 (1-7) and the number of litters per breeding season was 2.6 � 0.97 (1-5). In the latter half of pregnancy there was a linear relationship between the crown-rump length of foetuses and gestation length. Young were born naked, blind and with the pinnae folded forward with edges attached to the head. The upper incisors emerged at 4 days, the lower incisors at 6 days, the auditory meatus opened at about 10 days, the eyes opened at about 14 days, some solids were eaten and young were more independent at about 3 weeks of age, and they were weaned at about 29 days. Phases in the rate of increase in weight were associated with each of these developmental stages. Females were first capable of breeding at 124 days (433 g); most matured about 240 days in the season following that of their birth. The testes descended in males between 90 and 120 days (475 g) but full sperm production did not occur until about 130-140 days. Females could breed for three seasons (until about 3.5 y old). Placental scars were visible for up to 6 months, but had sometimes disappeared at 4 months post partum. Growth curves of tail and weight were sigmoid, and those of other body measurements were exponential, as in the Rattus group of Australian rodents, and differing from the pseudomyine rodents. Body measurements showed a sigmoid relationship to the linear equivalence of body weight. Developmental events occurred earlier, in relation to growth, in Hydromys and Rattus lutreolus than in Pseudomys novaehollandiae.

scholarly journals The attractive factor in the settlement of Ophelia bicornis Savigny

1954 ◽  
Vol 33 (2) ◽  
pp. 361-380 ◽  
Author(s):  
Douglas P. Wilson
Keyword(s):  
Breeding Season ◽  
Made In

Largely as a result of experiments made in 1951, sands were classed as attractive, neutral or repellent (Wilson, 1953 a); but only after the 1952 experiments had been completed did it become reasonably certain that the sands in which the larvae of Ophelia bicornis Savigny readily settle carry an attractive factor apparently distinct from a repellent one present in sands in which they will not settle (Wilson, 1953 b). Whilst the precise natures of the factors were uncertain, it seemed probable that they both derive from organic activity. The 1953 breeding season was devoted to an attempt to obtain more information about the attractive factor.

scholarly journals Diverse habitat use during two life stages of the critically endangered Bahama Oriole (Icterus northropi): community structure, foraging, and social interactions

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3500 ◽  
Author(s):  
Melissa R. Price ◽  
William K. Hayes
Keyword(s):  
Habitat Use ◽  
Social Interactions ◽  
Breeding Season ◽  
Pine Forest ◽  
Critically Endangered ◽  
Life Stages ◽  
Vegetation Types ◽  
Age Classes ◽  
Habitat Types ◽  
Second Year

Our ability to prevent extinction in declining populations often depends on effective management of habitats that are disturbed through wildfire, logging, agriculture, or development. In these disturbed landscapes, the juxtaposition of multiple habitat types can be especially important to fledglings and young birds, which may leave breeding grounds in human-altered habitat for different habitats nearby that provide increased foraging opportunities, reduced competition, and higher protection from predators. In this study, we evaluated the importance of three habitat types to two life stages of the critically endangered Bahama Oriole (Icterus northropi), a synanthropic songbird endemic to Andros, The Bahamas. First, we determined the avian species composition and relative abundance of I. northropi among three major vegetation types on Andros: Caribbean pine (Pinus caribaea) forest, coppice (broadleaf dry forest), and anthropogenic areas, dominated by nonnative vegetation (farmland and developed land). We then compared the foraging strategies and social interactions of two age classes of adult Bahama Orioles in relation to differential habitat use. Bird surveys late in the Bahama Oriole’s breeding season indicated the number of avian species and Bahama Oriole density were highest in coppice. Some bird species occurring in the coppice and pine forest were never observed in agricultural or residential areas, and may be at risk if human disturbance of pine forest and coppice increases, as is occurring at a rapid pace on Andros. During the breeding season, second-year (SY) adult Bahama Orioles foraged in all vegetation types, whereas after-second-year (ASY) adults were observed foraging only in anthropogenic areas, where the species nested largely in introduced coconut palms (Cocos nucifera). Additionally, SY adults foraging in anthropogenic areas were often observed with an ASY adult, suggesting divergent habitat use for younger, unpaired birds. Other aspects of foraging (vegetation features, food-gleaning behavior, and food items) were similar for the two age classes. Older Bahama Orioles exhibited relatively higher rates of social interactions (intraspecific and interspecific pooled) in anthropogenic areas, and won more interaction outcomes compared to younger adults. Our findings concur with those of other studies indicating dry broadleaf forest is vitally important to migrating, wintering, and resident birds, including the critically endangered Bahama Oriole, which appears to depend heavily on this vegetation type during certain life stages.

scholarly journals Dräktvariation hos hannar i skandinaviska populationer av svarthakad buskskvätta Saxicola rubicola

Ornis Svecica ◽  
2019 ◽  
Vol 29 ◽  
pp. 76-83
Author(s):  
Reino Andersson
Keyword(s):  
Breeding Season ◽  
Western Europe ◽  
Small Population ◽  
Genetic Differences ◽  
Lower Degree ◽  
British Isles ◽  
Individual Level ◽  
Norwegian Population ◽  
Large Distribution ◽  
Distribution In Europe

In western Europe, the European Stonechat Saxicola rubicola, occurs in two subspecies; rubicola, with a large distribution in Europe, and hibernans, mainly distributed on the British Isles. A small population of presumed hibernans birds breed in Norway. However, difficulties in distinguishing hibernans from rubicola at an individual level has led to speculation regarding the origin of the Norwegian birds. There are no clear genetic differences between the subspecies and their plumage appearance can be considered to overlap within parts of the range. To investigate this, I studied the plumage variation among males during the breeding season in the Scandinavian populations of European Stonechats in Sweden, Norway and Denmark. The study is based on photos of 404 males during the period March–May. The presence or absence of six typical hibernans characteristics were registered for each individual. The results show that males with both hibernans and rubicola characteristics occur during the spring in the Scandinavian populations. There was a clear over-representation of males with hibernans characteristics in Norway as compared to Sweden, and to a lower degree also to Denmark. If the expansion of rubicola progresses in Scandinavia, one could expect a larger proportion of rubicola-like males in the Norwegian population.

Status of the Critically Endangered Bengal Florican Houbaropsis bengalensis (Gmelin, 1789) in Koshi Tappu Wildlife Reserve, Nepal

2020 ◽  
Vol 12 (9) ◽  
pp. 16006-16012
Author(s):  
Hem Sagar Baral ◽  
Tek Raj Bhatt ◽  
Sailendra Raj Giri ◽  
Ashok Kumar Ram ◽  
Shyam Kumar Shah ◽  
...  
Keyword(s):  
Breeding Season ◽  
Indian Subcontinent ◽  
Critically Endangered ◽  
Adult Males ◽  
Black And White ◽  
Vegetation Height ◽  
Male Density ◽  
Comprehensive Survey ◽  
Management Recommendations ◽  
Wildlife Reserve

The Bengal Florican is one of the rarest bustard species and is listed ‘Critically Endangered’ by the IUCN.  The species is restricted to the lowland grasslands of India, Nepal, and Cambodia with fewer than 1,000 mature individuals.  To assess the species status in Koshi Tappu Wildlife Reserve, Nepal, we repeated our first comprehensive survey conducted during the 2012 breeding season.  In spite of a larger area coverage we recorded only 41 adult Bengal Floricans in 2017 compared to 47 individuals in 2012.  Detectability of this rare species is low in its Imperata-Saccharum grasslands.  We, therefore, used a long pole with black and white clothing to mimic Bengal Florican’s display flight to stimulate male Bengal Florican.  The number of adult males recorded was the same as in the 2012 survey and the adult male density remains one of the highest in the Indian subcontinent. Management recommendations for the long-term conservation of the species in Koshi Tappu include maintenance of Imperata-Saccharum grasslands in the reserve favoured by the Bengal Florican and working with farmers and communities adjacent to the reserve where the birds breed in order to maintain some agricultural lands with vegetation height suitable for the species especially during the species’ breeding season.

ADVANCE PLANNING FOR DISPERSANT USE/NON-USE

1985 ◽  
Vol 1985 (1) ◽  
pp. 429-432 ◽  
Author(s):  
J. P. Fraser
Keyword(s):  
Oil Spill ◽  
Oil Spills ◽  
State Of The Art ◽  
Geographical Area ◽  
The State ◽  
Environmental Damage ◽  
Advance Planning ◽  
Made In

ABSTRACT Guidelines are suggested for advance planning for the use or non-use of dispersants to combat oil spills. These guidelines are intended to expedite the decision to use dispersants in the event of an oil spill, where that will minimize environmental damage. These guidelines can be applied readily to any geographical area to answer the following questions: (1) Are there locations where dispersant application should normally be allowed? (2) In these locations, what rate of dispersant application should be allowed? (3) Are there locations where dispersant application should normally be avoided? The logic behind these guidelines is explained so that exceptions can be identified and so that changes in the guidelines can be made as advances are made in the state of the art. These guidelines provide for control over dispersant usage while allowing application (in most instances) at rates which can disperse floating oil effectively.

LECTOTYPIFICATION OF THE CRITICALLY ENDANGERED SUBSHRUB PHYLLANTHUS TALBOTII (PHYLLANTHACEAE)

2016 ◽  
Vol 73 (1) ◽  
pp. 133-138
Author(s):  
R. Kr. Singh ◽  
A. Garg
Keyword(s):  
Western Ghats ◽  
Critically Endangered ◽  
Wildlife Sanctuary ◽  
Threat Status ◽  
Conservation Measures ◽  
The Western Ghats ◽  
Made In

The critically endangered Phyllanthus talbotii Sedgw. (Phyllanthaceae) is endemic to the northern part of the Western Ghats in Goa and Karnataka, India. The species was described in 1921 from collections made in 1883, 1918 and 1919, and then rediscovered in 1969. We report here a new locality, Netravali Wildlife Sanctuary, South Goa district, Goa. The species is lectotypified and a detailed description is provided, including distribution, IUCN threat status, conservation measures and nomenclatural notes.

scholarly journals Diverse habitat use during two life stages of the critically Endangered Bahama Oriole (Icterus northropi): Community structure, foraging, and social interactions

2017 ◽  
Author(s):  
Melissa R Price ◽  
William K Hayes
Keyword(s):  
Habitat Use ◽  
Social Interactions ◽  
Breeding Season ◽  
Pine Forest ◽  
Critically Endangered ◽  
Foraging Strategies ◽  
Life Stages ◽  
Vegetation Types ◽  
Age Classes ◽  
Second Year

Our ability to prevent extinction in declining populations often depends on effective management of habitats that are disturbed through wildfire, logging, agriculture, or development. In these disturbed landscapes, the juxtaposition of multiple habitat types can be especially important to fledglings and young birds, which may leave breeding grounds in human-altered habitat for different habitats nearby that provide increased foraging opportunities, reduced competition, and higher protection from predators. In this study, we sought to better understand the importance of habitat diversity to two life stages of the critically endangered Bahama Oriole ( Icterus northropi ), a synanthropic songbird endemic to Andros, The Bahamas. First, we determined the avian species composition and relative abundance of the oriole among three major vegetation types on Andros: Caribbean pine ( Pinus caribaea ) forest, coppice (broadleaf dry forest), and anthropogenic areas, dominated by nonnative vegetation (farmland and developed land). We then compared the foraging strategies and social interactions of two age classes of adult orioles in relation to differential habitat use. Bird surveys late in the oriole’s breeding season indicated avian s pecies richness and oriole density were highest in coppice. Some bird species occurring in the coppice and pine forest were never observed in agricultural or residential areas, and may be at risk if human disturbance of pine forest and coppice increases, as is occurring at a rapid pace on Andros. During the breeding season, second-year (SY) adult orioles foraged in all vegetation types, whereas after-second-year (ASY) adults were observed foraging only in anthropogenic areas, where the species nested largely in introduced coconut palms ( Cocos nucifera ). Additionally, SY adults foraging in anthropogenic areas were often observed with an ASY adult, suggesting divergent habitat use for younger, unpaired birds. Other aspects of foraging (vegetation features, food-gleaning behavior, and food items) were similar for the two age classes. Older orioles exhibited relatively higher rates of social interactions (intraspecific and interspecific pooled) in anthropogenic areas, and won more interaction outcomes compared to youngeradults. Our findings concur with those of other studies indicating dry broadleaf forest is vitally important to migrating, wintering, and resident birds, including the critically endangered Bahama Oriole, which appears to depend heavily on this vegetation type during certain life stages.

Quantification of Net Environmental Benefit for Future Oil Spills

1999 ◽  
Vol 1999 (1) ◽  
pp. 619-627 ◽  
Author(s):  
Tim Lunel ◽  
Jenifer M. Baker
Keyword(s):  
Best Practice ◽  
Planning Process ◽  
Oil Spills ◽  
Quantitative Information ◽  
Environmental Benefits ◽  
Environmental Benefit ◽  
Immediate Feedback ◽  
Wide Range ◽  
The World ◽  
Made In

ABSTRACT Net Environmental Benefit Analysis (NEBA) is increasingly used as a framework to assess the environmental benefits and disadvantages of a chosen response action. This analysis can be used to account for political and economic impacts as well as the effects on the natural environment. Until recently the discussion has focused on qualitative assessments due to the lack of quantitative information collected at spills. This paper uses examples of best practice of NEBA from different spills around the world to outline the information that should be collected at future spills in order to determine the level of Net Environmental Benefit that has been achieved by the response operation. In the first instance immediate feedback may well provide information which aids decision making at the time of the incident. However, a key role for this information is also to enable responders around the world to establish best practice for a wide range of environmental sensitivities. Case histories of Net Environmental Benefits will provide a basis for the overall contingency planning process, recognising that post-spill decisions are best and most rapidly made in the light of pre-spill analyses, consultations and agreements by all the appropriate organisations.

scholarly journals Comparison of the Songs of Cassin’s and Plumbeous Vireos

Western Birds ◽  
2020 ◽  
Vol 51 (4) ◽  
pp. 293-306
Author(s):  
Edward R. Pandolfino ◽  
Chris Ray
Keyword(s):  
Breeding Season ◽  
False Positive ◽  
Full Range ◽  
Field Guides ◽  
Visual Identification ◽  
Made In

We compared the songs of Cassin’s (Vireo cassinii) and Plumbeous (V. plumbeus) Vireos to determine if there are characteristics that could allow one to confidently distinguish between these species by song. Using recordings made in the breeding season and within the undisputed breeding ranges of each species, away from the zone of contact, we compared five characteristics of a song: phrase length, rate of phrase delivery, proportion of frequency-modulated (buzzy) phrases, proportion of doubled phrases, and midpoint frequency between the highest and lowest frequencies of a phrase. Among these, the only character in which the species differed significantly was the average midpoint frequency of song phrases. Despite overlap between the species in the distribution of average midpoint frequency, a criterion of 3215 Hz allowed ~84% of the vireo songs in our sample to be identified correctly. We also tabulated expected proportions of true and false positive species identifications based on the full range of average midpoint frequencies likely to be encountered, finding that values >3410 Hz have a >95% probability of representing Cassin’s Vireo, and values <3050 have a >95% probability of representing the Plumbeous Vireo. Various field guides show conflicting breeding ranges for these species, and there are many field reports of both vireos outside their known breeding ranges in the breeding season. Given that visual identification of these birds in the field can be difficult when individuals are in faded spring/summer plumage, song may allow us to better define the actual limits of these species’ breeding ranges.

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