A direct comparison of trapping and spotlight searches for capturing Brown Tree Snakes on Guam

2001 ◽  
Vol 7 (1) ◽  
pp. 4 ◽  
Author(s):  
R. M. Engeman ◽  
D. S. Vice
Keyword(s):  
Forest Edge ◽  
Management Programme ◽  
Night Time ◽  
Brown Tree Snake ◽  
Population Reduction ◽  
Reduction Methods ◽  
Capture Method ◽  
Standard Practices ◽  
Brown Tree Snakes ◽  
Over Time

Brown Tree Snake populations on Guam are controlled in the vicinities of cargo staging and transport areas to prevent their dispersal from Guam, and their populations are controlled in areas where endangered species are to be reintroduced. Trapping and night-time spotlight searches of fences are the two primary Brown Tree Snake population reduction methods used on Guam. We conducted a three month study comparing Brown Tree Snake captures by spotlighting fences to captures by trapping. Traps were placed either on the edge of the forest paralleling the fences, or they were hung on the fences. Applications of each capture method followed the standard practices used within the operational programme charged with deterring the spread of Brown Tree Snakes from Guam. We found captures by trapping to exceed those by spotlighting each month, but the captures by trapping decreased substantially over time, while those by spotlighting did not. We detected no differences statistically between numbers of captures taken by traps hung on the forest edge versus those hung on the fences. We found no differences in sizes of Brown Tree Snakes captured by spotlighting and trapping, based on average snout-vent length (SVL) or the distribution of SVLs. We feel that the two capture methods complement each other in an integrated pest management programme.

scholarly journals Trapping strategies for deterring the spread of Brown Tree Snakes from Guam

1998 ◽  
Vol 4 (4) ◽  
pp. 348 ◽  
Author(s):  
Richard M. Engeman ◽  
Michael A. Linnell
Keyword(s):  
Pacific Islands ◽  
Health Hazard ◽  
Economic Problem ◽  
Planning Tool ◽  
Boiga Irregularis ◽  
Terrestrial Vertebrates ◽  
Brown Tree Snake ◽  
Brown Tree Snakes ◽  
Trap Placement ◽  
Accidental Introduction

The accidental introduction of the Brown Tree Snake Boiga irregularis to Guam has resulted in the extirpation of most of the island's native terrestrial vertebrates, has presented a health hazard to infants and children, and also has produced an economic problem. Prevention of its dispersal through Guam's cargo traffic to other Pacific islands has become a high environmental priority. Trapping around ports and other cargo staging areas is central to an integrated pest management programme designed to deter dispersal of the species. In this study, perimeter trapping of forested plots characteristic of those found in port areas was found to be the most effective trap placement strategy, although trap lines cut through the plot interior or placed along a single plot boundary were also effective. Snake removal potentially can be modelled using an exponential decay over time, providing the manager with a planning tool. Population recovery of Brown Tree Snakes in trapped plots was found to be slow in the fragmented forested habitats found around ports.

scholarly journals QUALITY, ANTIOXIDANT AND ENZYMATIC ACTIVITIES OF FACHEIRO (Pilosocereus pachycladus RITTER) FRUITS DURING MATURATION

2019 ◽  
Vol 32 (4) ◽  
pp. 1092-1103
Author(s):  
THIANE DE LIMA RODRIGUES ◽  
ALEX SANDRO BEZERRA DE SOUSA ◽  
MARIANY CRUZ ALVES DA SILVA ◽  
RICARDO DE SOUSA NASCIMENTO ◽  
FRANCISCO DE ASSYS ROMERO DA MOTA SOUSA ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Bioactive Compounds ◽  
Enzymatic Activities ◽  
Northeastern Brazil ◽  
Strongly Correlated ◽  
Dpph Radical ◽  
Functional Quality ◽  
Flat Shape ◽  
Capture Method ◽  
Over Time

ABSTRACT The fruit of Cactaceas from northeastern Brazil have been the object of many ethnobotanical and functional quality studies. However, a considerable number of species remain poorly exploited, such as the facheiro (Pilosocereus pachycladus Ritter), a native Brazilian plant widely occurring and used in the Caatinga. The objectives of this research were to evaluate the quality, and antioxidant and enzymatic activities of the facheiro fruit during maturation. Fruits were harvested from areas of occurrence of plants in the Paraíba State, Brazil, at three maturity stages, which were determined based on the color of the epicarp (G - green, IP - green with purple traces, and R - completely purple). It was carried out a survey of terms sensorial descriptor terms for fruit appearance and then evaluated the physical, physicochemical, bioactive compounds, antioxidant and peroxidase (POD) activities during maturation. The fruit were described as fleshy berries, with a smooth epicarp; a round, flat shape; opaque purple color; and juicy and soft pulp when ripe. Quality varied during maturation, with the most significant changes being in coloration: the fruit became more purple over time, providing a clear indicator of maturity. With maturation, there was an increase in the content of betalains and total extractable polyphenols, as well as antioxidant activity, by DPPH radical capture method, mainly in the pulp. The pulp of the Pilosocereus pachycladus fruit is an important source of betalains, primarily betacyanins. During maturation, POD activity decreased in the pericarp and increased in the pulp and was strongly correlated with the presence of betalains and with antioxidant activity.

Effectiveness of the detector dogs used for deterring the dispersal of Brown Tree Snakes

1998 ◽  
Vol 4 (3) ◽  
pp. 256 ◽  
Author(s):  
Richard M. Engeman ◽  
Daniel S. Vice ◽  
Danny V. Rodriguez ◽  
Kenneth S. Gruver ◽  
William S. Santos ◽  
...  
Keyword(s):  
Health Hazard ◽  
Infants And Children ◽  
Search Pattern ◽  
Economic Losses ◽  
Boiga Irregularis ◽  
Routine Procedure ◽  
Terrestrial Vertebrates ◽  
Brown Tree Snake ◽  
Brown Tree Snakes ◽  
Accidental Introduction

The accidental introduction of the Brown Tree Snake Boiga irregularis to Guam has resulted in the extirpation of most of the island's native terrestrial vertebrates, has created a health hazard to infants and children, and has resulted in economic losses. Cargo inspections using teams of handlers and their detector dogs form a last line of defense for preventing Brown Tree Snake dispersal from Guam. To assess the efficacy of the teams of handlers and their dogs for locating stowed Brown Tree Snakes, we planted Brown Tree Snakes (in escape-proof containers) in cargo without the knowledge of the handlers inspecting the cargo. We found that when an observer attended the inspection to monitor procedures, 80% of the planted snakes were located. Without an attending observer present, 70% of the planted snakes were discovered, but only after such plantings had become a routine procedure. Prior to the routine planting of snakes, efficacy was nearly 50% less (38%). The reasons some planted snakes were missed by the dog teams were split between: an insufficient search pattern by the handler, or the dog giving no discernable indication that a snake was present.

Patterns of seed rain and seedling regeneration in abandoned agricultural clearings in a seasonally dry tropical forest in India

2009 ◽  
Vol 26 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Karthik Teegalapalli ◽  
Ankila J. Hiremath ◽  
Devcharan Jathanna
Keyword(s):  
Tropical Forest ◽  
Tree Species ◽  
Forest Edge ◽  
Forest Recovery ◽  
Agricultural Fields ◽  
Chromolaena Odorata ◽  
Seasonally Dry Tropical Forest ◽  
Dry Tropical Forest ◽  
Seasonally Dry ◽  
Over Time

Abstract:Forest recovery in abandoned pastures and agricultural fields is often impeded, therefore it is important to understand the factors limiting regeneration. Patterns of seed arrival and regeneration in five abandoned agricultural clearings nested within a seasonally dry tropical forest in India were examined along five transects radiating from the forest edge into the clearings. Wind-dispersed seeds dominated the seed arrival in clearings compared with vertebrate-dispersed seeds: 5563 wind-dispersed seeds and 1094 vertebrate-dispersed seeds of 14 and 13 tree species, respectively, were recorded. Numbers of the former declined steeply with increasing distance from the forest, whereas the latter showed no evident pattern with distance. Seeds of the invasive herb, Chromolaena odorata, were abundant in clearings. Although wind-dispersed seeds greatly outnumbered vertebrate-dispersed seeds, seedlings and saplings of vertebrate-dispersed species were three times more abundant than those of wind-dispersed species, indicating distinct differences in patterns of actual and effective seed dispersal. This points to recruitment limitation, and suggests that seed arrival may not be the principal barrier to regeneration in these clearings. Nonetheless, the clearings are likely to revert to forest over time.

Morphology of the brown tree snake, Boiga irregularis, with a comparison of native and extralimital populations

2000 ◽  
Vol 48 (4) ◽  
pp. 357 ◽  
Author(s):  
Joan Whittier ◽  
Conrad Macrokanis ◽  
Robert T. Mason
Keyword(s):  
Solomon Islands ◽  
Natural Populations ◽  
Single Species ◽  
Morphological Characters ◽  
Nonparametric Analysis ◽  
Native Range ◽  
Boiga Irregularis ◽  
Brown Tree Snake ◽  
The Mean ◽  
Brown Tree Snakes

We conducted an analysis of the morphology of specimens of the brown tree snake, Boiga irregularis, from the native range of eastern and northern Australia, Papua New Guinea and the Solomon Islands. First, a cluster analysis was conducted to determine natural groupings in the data; however, no groupings based on morphological characters were found. Then the importance of additional factors such as geographical groupings and coloration was analysed in a nonparametric analysis of variance. Significant differences were found in the mean rankings of key characters such as dorsal mid-body, ventral and subcaudal scale counts. However, the amount of variation and the degree of overlap among populations and groupings precluded separating animals on the basis of these features. Our data support the recognition of a single species with two subspecies based on colour variation. We also compared the morphology of a sample of brown tree snakes from an extralimital population on Guam to that of this species in the areas of the native range. Our data supported suggestions of alliances of the Guam population with northern Papuan populations. However, the Guam population of the brown tree snake was found to be less variable than were localised natural populations. Morphologically, the Guam population is distinctive, suggesting that it has undergone significant morphological change since its introduction.

scholarly journals Provision of artificial shelter on beaches is associated with improved shorebird fledging success

2010 ◽  
Vol 21 (2) ◽  
pp. 172-185 ◽  
Author(s):  
GRAINNE S. MAGUIRE ◽  
ANDREW K. DUIVENVOORDEN ◽  
MICHAEL A. WESTON ◽  
ROBYN ADAMS
Keyword(s):  
Survival Rate ◽  
Thermal Insulation ◽  
Anthropogenic Disturbance ◽  
Survival Rates ◽  
Cost Effective ◽  
Management Programme ◽  
Fledging Success ◽  
Larger Sample ◽  
Over Time

SummaryArtificial chick shelters might improve productivity of beach-nesting birds threatened by anthropogenic disturbance. We investigated the efficacy of three different chick shelter designs against four criteria: accessibility to chicks over time, thermal insulation, conspicuousness to beach-goers, and practicality (cost and ease of transport). One design (‘A-frame’) was selected because it offered the greatest thermal insulation, was the least conspicuous, most cost effective, and performed equally well in terms of accessibility. We deployed these artificial shelters on Hooded Plover Thinornis rubricollis territories where broods were present (n = 11), and compared the behaviour and survival rate of chicks to that at control sites (n = 10). We were unable to discern any difference in the behaviour of broods when artificial shelters were available. However, the survival rate of chicks to fledging was 71.8% higher where an artificial shelter was provided (n = 21 broods). This was validated by analysing data from a larger sample of broods monitored as part of an active volunteer-based management programme; shelters conferred a 42.8% increase in survival to fledging (n = 81 broods). Thus, artificial shelters have the potential to increase survival rates of threatened shorebird chicks, though the mechanisms through which survival is increased require further investigation.

Stimulus control of predatory attack in the brown tree snake (Boiga irregularis)

1988 ◽  
Vol 9 (1) ◽  
pp. 77-88 ◽  
Author(s):  
Hobart M. Smith ◽  
Karl Kandler ◽  
Robert Lee ◽  
David Chiszar
Keyword(s):  
Stimulus Control ◽  
Chemical Cues ◽  
Boiga Irregularis ◽  
Choice Behaviour ◽  
Volatile Chemicals ◽  
Brown Tree Snake ◽  
Predatory Attack ◽  
Brown Tree Snakes

AbstractThree experiments studied predation upon neonatal rodents by brown tree snakes (Boiga irregularis). Experiment 1 showed that chemical cues arising from prey were used in foraging tests that could not be completed on the basis of vision alone. Experiment 2 provided only airborne chemical cues, and snakes performed at chance levels in selecting among odoriferous (baited) and non-odoriferous (unbaited) nests. Snakes performed above chance, however, when a chemical trail led to the baited nest (Experiment 3), suggesting that non-volatile chemicals are most important in guiding choice behaviour.

Guam, the Brown Tree Snake Invasion, and Suicide Prevention

2011 ◽  
Vol 1 (1) ◽  
pp. 11-14
Author(s):  
Robert F. Morgan
Keyword(s):  
Suicide Prevention ◽  
Chaos Theory ◽  
Cultural Adaptation ◽  
High Profile ◽  
Brown Tree Snake ◽  
Brown Tree Snakes

A sample of vignettes from past and present psychological applications in tropical Guam with an assist from contemporary Singapore. An emphasis on cultural adaptation to an invasion of brown tree snakes is followed by antidotes to teen suicide subsequent a high profile suicidal event. A chaos theory perspective is suggested.

scholarly journals Impact of highway on vertebrate roadkill in Nam Nao National Park, Thailand

2020 ◽  
Vol 21 (11) ◽  
Author(s):  
Wuttisak Kummoo ◽  
Jiraporn Teampanpong ◽  
Pantiya Utsa ◽  
Paanwaris Paansri ◽  
Warong Suksavate ◽  
...  
Keyword(s):  
National Park ◽  
Management Strategies ◽  
Biodiversity Loss ◽  
Forest Edge ◽  
Mitigation Strategies ◽  
Limited Attention ◽  
Road Mortality ◽  
Night Time ◽  
The Road ◽  
Taxonomic Groups

Abstract. Kummoo W, Teampanpong J, Paansri P, Suksavate W, Utsa P, Duengkae P, Prompat S. 2020. Impact of highway on vertebrate roadkill in Nam Nao National Park, Thailand. Biodiversitas 21: 5540-5550. Roads lead to biodiversity loss, primarily through wildlife collisions. This phenomenon is widespread, despite limited attention in Thailand. To reduce road mortality, the roadkilled species and their distributions along the road become a significant component for designing management strategies. We surveyed vertebrate mortality covering 44 kilometers of Highway 12, passing through Nam Nao Nation Park in Phetchabun Province of Thailand for 34 replicates between August 2018 and July 2019. We recorded 1,389 carcasses of 578 amphibians, 540 reptiles, 190 mammals and 81 birds. The rate of wildlife-vehicle collisions (WVCs) was 1.089 ± 0.823 carcasses-km-1day-1, comprised mostly of amphibians. The distribution pattern of WVCs was arranged in spatial clusters. Five wildlife collision hotspots for four taxa groups were identified. Overall, the WVC presence was positively associated with vegetation types but negatively associated with distance to the forest edge, the presence of road barriers and the number of road lane. Concurrently, the numbers of roadkill incidents were positively associated with amphibians more than other vertebrate groups, the night time and number of daily vehicles. Our results suggest that WVC rates on HW12 vary among taxonomic groups, temporal scales and environmental factors. It highlights key hotspots where mitigation strategies should be implemented for biodiversity conservation.

scholarly journals The effect of time on qualitative compliance in brace treatment for AIS

2008 ◽  
Vol 32 (2) ◽  
pp. 136-144 ◽  
Author(s):  
Ian Mak ◽  
Edmond Lou ◽  
James V. Raso ◽  
Doug L. Hill ◽  
Eric Parent ◽  
...  
Keyword(s):  
Idiopathic Scoliosis ◽  
Cobb Angle ◽  
Treatment Method ◽  
Monitor System ◽  
Brace Treatment ◽  
Time Analysis ◽  
Night Time ◽  
Angle Measurements ◽  
Non Surgical Treatment ◽  
Over Time

Brace treatment is the most commonly used non-surgical treatment method for adolescent idiopathic scoliosis (AIS). This study is to determine the force changes exerted by a brace over time during both day and night-time wear and to explore correlations between force changes to bracing outcomes. Twenty subjects (three male, 17 female) diagnosed with idiopathic scoliosis who had worn their braces for six months participated into this study. However, due to non-continuous brace wear and exclusion of subjects with large curves (Cobb angle >40°), only nine subjects were included into the day-time analysis and 11 subjects were included into night-time analysis. All subjects used a load monitor system from four days up to 14 days with Boston braces. Cobb angle measurements were taken at initiation of brace treatment as well as after weaning upon completion of the treatment. After the monitoring period, the data was extracted and analyzed. Forces were compared between hours 1, 2, and 5 for the day and night groups, and the correlation of force changes to bracing outcomes were analyzed. In daytime wear, a significant decrease in force over time was found. Most of the decrease occurred within hours 1 and 2 of brace wear. There was no significant decrease during night wear. There were no significant correlations between force decline and outcome.

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