Estimating brown bear abundance and harvest rate on the southern Alaska Peninsula

Abundance estimation of hunted brown bear populations should occur on the same geographic scale as harvest data analyses for estimation of harvest rate. Estimated harvest rates are an important statistic for managing hunted bear populations. In Alaska, harvest data is collected over large geographic units, called Game Management Units (GMUs) and sub-GMUs. These sub GMUs often exceed 10,000 km2. In the spring of 2002, we conducted an aerial survey of GMU 9D (12,600 km2) and GMU 10 (4,070 km2) using distance sampling with mark-resight data. We used a mark-resight distance sampling method with a two-piece normal detection function to estimate brown bear abundance as 1,682.9 (SE = 174.29) and 316.9 (SE = 48.25) for GMU 9D and GMU 10, respectively. We used reported hunter harvest to estimate harvest rates of 4.35% (SE = 0.45%) and 3.06% (SE = 0.47%) for GMU 9D and GMU 10, respectively. Management objective for these units support sustained, high quality hunting opportunity which harvest data indicate are met with an annual harvest rate of approximately 5–6% or less.

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Estimating red deer abundance using the pellet-based distance sampling method

Journal of Forest Science ◽

10.17221/52/2015-jfs ◽

2016 ◽

Vol 61 (No. 10) ◽

pp. 422-430 ◽

Cited By ~ 1

Author(s):

Torres RT ◽

Valente AM ◽

Marques TA ◽

C. Fonseca

Keyword(s):

Sampling Method ◽

Red Deer ◽

Distance Sampling

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Evaluation of line-transect sampling for estimating koala abundance in the Pine Rivers Shire, south-east Queensland

Wildlife Research ◽

10.1071/wr02042 ◽

2003 ◽

Vol 30 (2) ◽

pp. 127 ◽

Cited By ~ 17

Author(s):

David S. Dique ◽

Deidré L. de Villiers ◽

Harriet J. Preece

Keyword(s):

Confidence Interval ◽

Distance Sampling ◽

Line Transect ◽

Similar Estimate ◽

Line Transect Sampling ◽

Detection Function ◽

Pilot Survey ◽

Transect Sampling ◽

Line Transects ◽

Urban Sites

Distance sampling using line transects has not been previously used or tested for estimating koala abundance. In July 2001, a pilot survey was conducted to compare the use of line transects with strip transects for estimating koala abundance. Both methods provided a similar estimate of density. On the basis of the results of the pilot survey, the distribution and abundance of koalas in the Pine Rivers Shire, south-east Queensland, was determined using line-transect sampling. In total, 134 lines (length 64 km) were used to sample bushland areas. Eighty-two independent koalas were sighted. Analysis of the frequency distribution of sighting distances using the software program DISTANCE enabled a global detection function to be estimated for survey sites in bushland areas across the Shire. Abundance in urban parts of the Shire was estimated from densities obtained from total counts at eight urban sites that ranged from 26 to 51 ha in size. Koala abundance in the Pine Rivers Shire was estimated at 4584 (95% confidence interval, 4040–5247). Line-transect sampling is a useful method for estimating koala abundance provided experienced koala observers are used when conducting surveys.

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Aerial line transect survey to estimate abundance of marsh deer (Blastocerus dichotomus) (Illiger, 1815)

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89132005000600017 ◽

2005 ◽

Vol 48 (5) ◽

pp. 807-814 ◽

Cited By ~ 9

Author(s):

Artur Andriolo ◽

Ubiratan Piovezan ◽

Mateus José Rodrigues Paranhos da Costa ◽

Jeff Laake ◽

José Maurício Barbanti Duarte

Keyword(s):

Population Size ◽

River Basin ◽

Distance Sampling ◽

Aerial Survey ◽

Line Transect ◽

Sampling Methodology ◽

Future Analysis ◽

Line Transect Survey ◽

Blastocerus Dichotomus ◽

The Impact

The objective was to estimate abundance of marsh deer in the Paraná River basin of this work. The results provided information to support further analysis of the impact of the Porto Primavera flooding lake over population. Sixty-nine animals were recorded by aerial survey using distance sampling methodology. Animals were widely distributed throughout the study area. The uncorrected data resulted in a estimate density of 0.0035 ind/ha and a population size of 636 individuals. Correcting the g for the animals that could be missed the calculated abundance was 896 (CV=0.27) individuals. This methodology was applied with success to survey marsh deer. The result was important to evaluate the marsh deer status in the area, and for future analysis of the impact of the flooding dam.

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ESTIMASI KEPADATAN ULAT API MELALUI METODE SAMPLING JARAK

Jurnal Optimalisasi ◽

10.35308/jopt.v3i4.270 ◽

2018 ◽

Vol 3 (4) ◽

Author(s):

Cukri Rahmi Niani

Keyword(s):

Oil Palm ◽

Sampling Method ◽

Distance Sampling ◽

Sampling Techniques ◽

Sampling Distance ◽

Setora Nitens

Many types of pests which is found in oil palm plantations such as rats, bees and the caterpillars. Caterpillar and the bagworm, including a caterpillar eaters leaves oil palm plantations. This Research focuses on a caterpillar type Setora nitens at oil palm plantations Karya Tanah Subur in West Aceh. Many ways that has been done to overcome pests caterpillar in oil palm plantations from early monitoring and extermination caterpillar. To know the density caterpillar can be done by counting directly individual caterpillar or with other methods that in this research, the density caterpillar in the estimation through distance sampling techniques. Distance sampling is one of the methods used to estimate the density and the spread population. The sampling distance, a series point or lines are placed randomly on the districts census and measured the distance between individuals who were detected in handcuffs or this point. Ordered Distance, Point Quarter and Variable Area Transect the distance sampling method that used in the research. Based on the explanation, an extensive microinsurance is focused on the estimation density caterpillar using the distance sampling methods.Keywords: Setora nitens, Distance Sampling, Order Distance, Point Quarter, VariableArea Transect.

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Abundance Estimation of the Finless Porpoise, Neophocaena phocaenoides, Using Models of the Detection Function in a Line Transect

Korean Journal of Fisheries and Aquatic Sciences ◽

10.5657/kfas.2007.40.4.201 ◽

2007 ◽

Vol 40 (4) ◽

pp. 201-209 ◽

Cited By ~ 6

Author(s):

Kyum-Joon Park ◽

Zang-Geun Kim ◽

Chang-Ik Zhang

Keyword(s):

Abundance Estimation ◽

Line Transect ◽

Finless Porpoise ◽

Detection Function ◽

Neophocaena Phocaenoides

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Demographic trends of a reintroduced Iberian ibex Capra pyrenaica victoriae population in central Spain

Mammalia ◽

10.1515/mammalia-2013-0141 ◽

2014 ◽

Vol 0 (0) ◽

Cited By ~ 1

Author(s):

Pablo Refoyo ◽

Cristina Olmedo ◽

Ignacio Polo ◽

Paulino Fandos ◽

Benito Muñoz

Keyword(s):

National Park ◽

Sampling Method ◽

Distance Sampling ◽

Central Spain ◽

Capra Pyrenaica ◽

Demographic Trends ◽

Iberian Ibex ◽

Reintroduced Population

AbstractOne reintroduced population of Iberian ibex was monitored between 2000 and 2007 in the Sierra de Guadarrama National Park (Central Spain) using the distance sampling method. The densities obtained from three samplings show a significant increase between 2000 (6.57 ind./km

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Can trackers count free-ranging wildlife as effectively and efficiently as conventional aerial survey and distance sampling? Implications for citizen science in the Kalahari, Botswana

Biological Conservation ◽

10.1016/j.biocon.2018.04.027 ◽

2018 ◽

Vol 223 ◽

pp. 156-169 ◽

Cited By ~ 4

Author(s):

Derek Keeping ◽

Julia H. Burger ◽

Amo O. Keitsile ◽

Marie-Charlotte Gielen ◽

Edwin Mudongo ◽

...

Keyword(s):

Citizen Science ◽

Distance Sampling ◽

Aerial Survey ◽

Free Ranging

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Estimating the abundance of the bilby (Macrotis lagotis): a vulnerable, uncommon, nocturnal marsupial

Australian Mammalogy ◽

10.1071/am14024 ◽

2015 ◽

Vol 37 (1) ◽

pp. 75 ◽

Cited By ~ 12

Author(s):

Gregory William Lollback ◽

Rachel Mebberson ◽

Niki Evans ◽

Jonathan David Shuker ◽

Jean-Marc Hero

Keyword(s):

National Park ◽

Distance Sampling ◽

Abundance Estimation ◽

Dramatic Decrease ◽

South West ◽

Population Crash ◽

Pellet Density ◽

Long Term Monitoring ◽

Term Monitoring

The bilby (Macrotis lagotis) is listed as Vulnerable in Australia, is strictly nocturnal and shy, and it has proven difficult to estimate its population abundance. The aim of this study was to determine methodology that would reliably estimate the abundance of the bilby within an enclosure at Currawinya National Park, south-west Queensland. We estimated the abundance of bilbies on long-term monitoring plots by counting pellets comparing two methods: counting standing odorous pellets using distance sampling and counting newly deposited pellets (FAR). Pellet deposition rate and decay rate were also estimated to enable population estimation using distance sampling. The density of odorous (<14 days old) standing pellets and old pellets was highest in October 2011 and dropped dramatically when plots were revisited in March 2012 and July 2012. Counting standing pellets using distance sampling provided a rigorous estimate of abundance of bilbies at Currawinya. Bilby density and pellet deposition rates were too low for the FAR method to accurately or precisely estimate bilby density. A population crash within the enclosure following an invasion of feral cats was mirrored by a dramatic decrease in pellet density. Incorporating detectability into abundance estimation should be carefully considered for conservation purposes.

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Mongolian Gobi supports the world's largest populations of khulan Equus hemionus and goitered gazelles Gazella subgutturosa

Oryx ◽

10.1017/s0030605316000417 ◽

2016 ◽

Vol 51 (4) ◽

pp. 639-647 ◽

Cited By ~ 7

Author(s):

B. Buuveibaatar ◽

S. Strindberg ◽

P. Kaczensky ◽

J. Payne ◽

B. Chimeddorj ◽

...

Keyword(s):

Distance Sampling ◽

Aerial Survey ◽

Desert Ecosystem ◽

Gobi Desert ◽

Anthropogenic Pressure ◽

Abundance Estimates ◽

Equus Hemionus ◽

The Status ◽

Wild Ass ◽

Gazella Subgutturosa

AbstractMongolia's Gobi Desert ecosystem, a stronghold for populations of the Asiatic wild ass (khulan) Equus hemionus and the goitered gazelle Gazella subgutturosa, faces conservation challenges as a result of rapid economic development, including mining-related infrastructure projects. There is a paucity of reliable data on population abundance for these ungulates in the region, which makes it difficult to assess how they are responding to increasing anthropogenic pressure. Our aim was to obtain abundance estimates for khulan and goitered gazelles to inform their management and form the basis of a long-term monitoring programme. Each year during 2012–2015 we surveyed a total of 64 line transects spaced 20 km apart, with a total of 3,464 km of survey effort across 78,717 km2. Distance sampling analysis provided annual estimates of density and abundance, which were cross-referenced with the results of an aerial survey conducted in 2013. Overall, we observed 784 groups (14,608 individuals) of khulan and 1,033 groups (3,955 individuals) of goitered gazelles during the four surveys. The abundance estimates for 2013 were 35,899 (95% CI 22,680–40,537) khulan and 28,462 (95% CI 21,326–37,987) goitered gazelles. These estimates were congruent with the results from the aerial survey, which overlapped spatially and temporally with our ground-based survey. Our findings confirm that Mongolia's Gobi Desert supports the largest population of khulan and goitered gazelles in the world, and we provide a critical update on the status of the two species.

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