• Title/Summary/Keyword: Minimum convex polygon

Search Result 31, Processing Time 0.025 seconds

Territory Size of Breeding Chinese Sparrowhawks($Accipiter$ $soloensis$) in Korea (붉은배새매($Accipiter$ $soloensis$)의 번식기 세력권 추정)

  • Choi, Chang-Yong;Nam, Hyun-Young;Lee, Woo-Shin
    • Korean Journal of Environment and Ecology
    • /
    • v.26 no.2
    • /
    • pp.186-191
    • /
    • 2012
  • The Chinese Sparrowhawk($Accipiter$ $soloensis$) is the most common breeding raptor in Korea, but its spatial use in the breeding season has been poorly documented. Therefore, to estimate the territory and home range sizes of breeding sparrowhawks, six territorial males(four in 2005 and two in 2006) were observed from June to July in Gyeonggi Province, the Republic of Korea. Main perches, which were used repeatedly(more than three times) or where apparent territorial behaviors were observed, were identified and the locations were analyzed by GIS software. According to the 100% Minimum Convex Polygons which were identified from $25.2{\pm}5.3$ perches, Chinese Sparrowhawks occupied $4.62{\pm}0.90$ ha for breeding territories and used $22.57{\pm}5.12$ ha for their home ranges. These estimates showed larger spatially occupied areas than those in one previous report, but this study suggests that Chinese Sparrowhawks intensively use small areas throughout the breeding season. This result also implies that the sparrowhawks have the potential to be significantly affected by any habitat changes and resource exploitation in the small areas(particularly in small rice paddies of 0.6-2.0 ha) which they largely rely on for food. Although this study was based on observations solely for territory size estimations, this study may be worthwhile as preliminary pilot research for Chinese Sparrowhawk conservation, management, and further studies.

Study on the Home-range and Winter Habitat Pintail using the Wild-Tracker (WT-300) in Korea (WT-300을 이용한 월동기 고방오리(Anas acuta)의 행동권 및 서식지 이용연구)

  • Jung, Sang-Min;Shin, Man-Seok;Cho, Hae-jin;Han, Seung-Woo;Son, Han-Mo;Kim, Jeong Won;Kang, Sung-Il;Lee, Han-soo;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
    • /
    • v.33 no.1
    • /
    • pp.1-8
    • /
    • 2019
  • Pintail (Anas acuta) is the major wintering bird in South Korea and known as a major mediator of the highly pathogenic avian influenza (HPAI). Pintail migrates long distances between Russian Siberia and Korea. This species prefers a rice paddy area as their winter habitat. The purpose of this study is to provide the data necessary for the conservation and management of bird habitats in Korea by understanding the wintering home-range and habitat of pintail in Korea. We captured six pintails using a cannon-net in the winter of 2015 and attached the GPS-mobile phone based telemetry (WT-300) on them to study the wintering home-range and wintering habitat. We analyzed the tracking location data using ArcGIS 9.0 Animal Movement Extension and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range in the wintering ground analyzed by MCP was $677.3km^2$ (SD=130.2, n=6) while the maximum and minimum were $847.7km^2$ and $467.5km^2$, respectively. Extents of home-range analyzed by KDE were $194.7km^2$ (KDE 90%), $77.4km^2$ (KDE 70%), and $35.3km^2$ (KDE 50%). The pintails mostly used both sea and paddy field as habitat in the winter season and utilized paddy fields more during the nighttime and than the daytime. We concluded that the home-range and habitat of pintails in the winter could be used as the reference data for the preservation of species, management of habitats, and coping with a breakout of HPAI.

Assessing the Carrying Capacity of Wild Boars in the Bukhansan National Park using MaxEnt and HexSim Models

  • Tae Geun Kim
    • Proceedings of the National Institute of Ecology of the Republic of Korea
    • /
    • v.4 no.3
    • /
    • pp.115-126
    • /
    • 2023
  • Understanding the carrying capacity of a habitat is crucial for effectively managing populations of wild boars (Sus scrofa), which are designated as harmful wild animal species in national parks. Carrying capacity refers to the maximum population size supported by a park's environmental conditions. This study aimed to estimate the appropriate wild boar population size by integrating population characteristics and habitat suitability for wild boars in the Bukhansan National Park using the HexSim program. Population characteristics included age, survival, reproduction, and movement. Habitat suitability, which reflects prospecting and resource acquisition, was determined using the Maximum Entropy model. This study found that the optimal population size for wild boar ranged from 217 to 254 individuals. The population size varied depending on the amount of resources available within the home range, indicating fewer individuals in a larger home range. The estimated wild boar population size was 217 individuals for the minimum amount of resources (50% minimum convex polygon [MCP] home range), 225 individuals for the average amount of resources (95% MCP home range), and 254 individuals for the maximum amount of resources (100% MCP home range). The results of one-way analysis of variance revealed a significant difference in wild boar population size based on the amount of resources within the home range. These findings provide a basis for the development and implementation of effective management strategies for wild boar populations.

Interzonal Comparative Analysis of the Wintering Habitat of Spot-billed Duck (Anas poecilorhyncha) (흰뺨검둥오리의 지역간 월동서식지이용 비교분석)

  • Hwang, Jong-Kyeong;Shin, Man-Seok;Kang, Young-Myong;Yoom, Hachung;Choi, Jida;Jeong, Wooseog;Lee, Jun-Woo
    • Korean Journal of Environment and Ecology
    • /
    • v.30 no.4
    • /
    • pp.676-683
    • /
    • 2016
  • This study was conducted using the Wild -Tracker (WT-300, GPS-Mobile Phone Based Telemetry KoEco) to understand the habitats of the spot-billed duck wintering in urban and rural areas and provide the results as the basic data for the protection and management of the habitats of the waterbirds in Korea. Study areas consisted of the Anseong stream in Gyeonggi-do and the Sansu reservoir in Haenam. Five spot-billed ducks were captured by region, and we attached Wild-Tracker to each of the spot-billed ducks. We analyzed the tracking location data using ArcGIS 9.x and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range measured by MCP was $250.8km^2$(SD=195.3, n=5) in Anseong and was $89.1km^2$ (SD=69.6, n=5) in Haenam. 50% home-range measured by KDE was $21.8km^2$ (SD=26.9, n=5) in Anseong and $3.5km^2$ (SD=2.2, n=5) in Haenam, indicating a narrow home range in Haenam. During the winter season, both wetland and paddy field were mostly used as habitats in Anseong and Haenam. While the paddy field utilization rate was high in the daytime in Haenam, it was high in the nighttime in Anseong. By late winter, Haenam's day time paddy field utilization rate and Anseong's night time paddy field utilization rate increased.

Development and Application of a Program Using Sphinx Puzzle for the Mathematically Gifted Elementary Students (초등수학영재를 위한 스핑크스 퍼즐 프로그램 개발과 적용사례)

  • Hwang, Ji Nam
    • Journal of Gifted/Talented Education
    • /
    • v.27 no.1
    • /
    • pp.37-57
    • /
    • 2017
  • In terms of making more various geometrical figures than existing Tangram, Sphinx Puzzle has been used as a material for the gifted education. The main research subject of this paper is to verify how many convex polygons can be made by all pieces of a Sphinx Puzzle. There are several previous researches which dealt with this research subject, but they did not account for the clear reasons on the elementary level. In this thesis, I suggest using unit area and minimum area which can be proved on the elementary levels to account for this research subject. Also, I composed the program for the mathematically gifted elementary students, regarding the subject. I figured out whether they can make the mathematical justifications. I applied this program for three 6th grade students who are in the gifted class of the G district office of education. As a consequence, I found that it is possible for some mathematically gifted elementary students to justify that the number of convex polygons that can be made by a Sphinx Puzzle is at best 27 on elementary level.

A Study on the Effective Use of Tangrams for the Mathematical Justification of the Gifted Elementary Students (초등수학영재의 수학적 정당화를 위한 칠교판 활용방안 연구)

  • Hwang, Jinam
    • Journal of Elementary Mathematics Education in Korea
    • /
    • v.19 no.4
    • /
    • pp.589-608
    • /
    • 2015
  • The inquiry subject of this paper is the number of convex polygons one can form by attaching the seven pieces of a tangram. This was identified by two mathematical proofs. One is by using Pick's Theorem and the other is 和々草's method, but they are difficult for elementary students because they are part of the middle school curriculum. This paper suggests new methods, by using unit area and the minimum area which can be applied at the elementary level. Development of programs for the mathematically gifted elementary students can be composed of 4 class times to see if they can prove it by using new methods. Five mathematically gifted 5th grade students, who belonged to the gifted class in an elementary school participated in this program. The research results showed that the students can justify the number of convex polygons by attaching edgewise seven pieces of tangrams.

Characteristics of the Home Range and Habitat Use of the Greater Horseshoe Bat (Rhinolophus ferrumequinum) in an Urban Landscape (도심 경관에 서식하는 관박쥐의 행동권 및 서식지 이용 특성)

  • Jeon, Young Shin;Kim, Sung Chul;Han, Sang Hoon;Chung, Chul Un
    • Journal of Environmental Science International
    • /
    • v.27 no.8
    • /
    • pp.665-675
    • /
    • 2018
  • The purpose of this study was to identify the characteristics of the home range and habitat use of Rhinolophus ferrumequinum individuals that inhabit urban areas. The bats were tracked using GPS tags. For analysis of the home rage, Minimum Convex Polygon (MCP) and Kernel Home Range (KHR) methods were used. The landscape types of all positional information were analyzed using ArcGIS 9.3.1 (ESRI Inc.). The average home range of 16 R. ferrumequinum individuals was $68.63{\pm}25.23ha$, and the size of the overall home range for the females ($85.49{\pm}25.40ha$) was larger than that for the males ($51.76{\pm}8.30ha$). The highest average home range for the males was found in August ($61.21{\pm}0.01ha$), whereas that for the females was found in September ($112.27{\pm}5.94ha$). The size of 50% KHR ranged from a minimum of 13.26 ha to a maximum of 31.00 for the males and a minimum of 8.02 ha to a maxinum of 42.16 ha for the females, showing no significant differences between the two sexes. In addition, males and females showed no differences in the size of 50% KHR in the monthly comparisons. However, the females showed differences in the size of their core area between periods before and after giving birth. The comparisons between 100% MCP and 50% KHR showed that the types of habitats used by R. ferrumequinum were mostly forest areas, including some farmlands. In addition, comparisons with a land cover map showed that the proportion of broad-leaved forests was the highest, followed by that of mixed forests.

Patterns of Habitat Use and Home Range of a GPS Tracking White-naped Crane Grus vipio in Cheorwon, Korea

  • Lee, Kisup;Kwon, In-Ki
    • Proceedings of the National Institute of Ecology of the Republic of Korea
    • /
    • v.2 no.4
    • /
    • pp.285-292
    • /
    • 2021
  • We investigated habitat use and home range of a rescued and released white-naped crane using GPS tracking technology in Cheorwon, South Korea, from October 2016 to March 2017. Four types of roosting sites were identified: frozen reservoirs, paddy fields, rivers, and wetlands. Upon arrival, the white-naped crane preferred wetlands in the Demilitarized Zone (DMZ). In late wintering season, it showed a tendency to change main roosting sites in the following order: rice paddies, rivers, and frozen reservoirs. Among 14 sleeping places, Civilian Control Zone (CCZ) with various type of available habitats was more preferred than the DMZ. Places outside of CCZ were rarely used due to anthropogenic disturbances during the night. The tracked white-naped crane widely chose daytime feeding sites while moving around all over rice paddies in the CCZ. Mean diurnal movement distance was 10.5 km with a maximum of 24.8 km. Its home range measured with Minimum Convex Polygon (MCP) and Kernel Density Estimation (KDE) was 172.30 km2 with MCP, 159.60 km2 with KDE 95%, 132.48 km2 with KDE 90%, and 42.45 km2 with KDE 50%. All estimated values of home ranges were higher in the early and later winter than those in the middle period.

Analysis of Home Range of Asiatic Black Bear Released in Jirisan National Park (지리산국립공원에 방사된 반달가슴곰의 행동권 분석)

  • Kim, Jeong-Jin;Kim, Sun-Do;Kang, Jae-Gu;Kim, Jong-Kab;Moon, Hyun-Shik
    • Journal of agriculture & life science
    • /
    • v.45 no.5
    • /
    • pp.41-47
    • /
    • 2011
  • This study was carried out to provide basic information for assessment conditions as habitat to conserve and restore asiatic black bear released in Jirisan National Park. The field investigation at Piagol, Bitjeom, Jangdanggol, Baemsagol, Chilseon valley, and Hanshin valley which checked for habitat of released asiatic black bear were conducted from 2008 to 2010. There were no obvious differences in home range size of asiatic black bear by study year. The seasonal home ranges were analyzed $25.64km^2$ for males and $17.57km^2$ for female in spring, $73.02km^2$ for males and $27.45km^2$ for females in summer, $41.58km^2$ for males and $13.26km^2$ for females in fall, and $6.11km^2$ for males and $2.89km^2$ for females in winter based on 95% Minimum Convex Polygon (MCP) method, respectively. In average elevation by gender of asiatic black bear, the male was higher than the female. respectively. Average elevation by season were $894{\pm}33m$ in spring, $852{\pm}20m$ in summer, $985{\pm}67m$ in fall, and $996{\pm}26m$ in winter, respectively.

Movement patterns and home range of captive-bred Amur ratsnake (Elaphe schrenckii) juveniles in the natural habitat

  • Kim, Dae-In;Kim, Il-Hoon;Kim, Ja-Kyeong;Kim, Bin-Na;Park, Dae-Sik
    • Journal of Ecology and Environment
    • /
    • v.35 no.1
    • /
    • pp.41-50
    • /
    • 2012
  • To determine the movement patterns, home range, and use of structural features of captive-bred one- or two-year-old Amur ratsnake (Elaphe schrenckii) juveniles in the natural habitat, we radio-tracked a total of 11 juvenile snakes in a mountain valley in Chiaksan National Park, South Korea, between August 21 and September 20, 2010 and between June 13 and July 13, 2011. During the first week of the release, most juveniles moved short distances, daily, but they increased their distances after the first week. The body weight of the juveniles was negatively related with the movement rate (dividing the number of movements by the number of relocations), which was positively related with the mean daily distances moved and the size of both a kernel 50% and 95% home range. During the study period, the juveniles moved daily, approximately 17 m, and the size of the minimum convex polygon and the 50% and 95% kernel home ranges were 1.8 ha, 0.4 ha, and 3.0 ha, respectively. The released captive-bred juveniles were more frequently confirmed underground or on the ground rather than on rocks or on trees. Our results suggest that the body condition of released individuals, the seasonal time of the release, and the existence of available prey and shelters in the habitat should be carefully considered when releasing captive-bred Amur ratsnake juveniles for the rehabilitation of field populations.