Influence of white-tailed deer population density on vegetation standing crop in a semiarid environment

The paper presents the current methods of management and environmental conditions of the functioning of red deer population on the Wolin Island. The inventory carried out in 2014 using the drive census method revealed the prevalence of stags in the population (0.86 hinds/1stag) and the population density of 225 individuals/1,000 hectares of the forest, whereas harvest conducted in this season showed merely 22 individuals/1,000 hectares. In the analysed seasons before the inventory, harvest was also low (about 10% of the probable actual state) and despite harvesting mainly hinds, it did not curb the population growth. In the years 2006 – 2014, the yearly harvest in the largest hunting district fluctuated within the range of 14.5 to 60.5, x̅=27.0 individuals/1,000 hectares (n=9), while in the remaining four smaller population management units, the average yearly harvest amounted to only 0.2 to 9.8 individuals/1,000 hectares (n=9). The realized rate of population growth determined by the method of summer deer observation in 2015 amounted to 42.2% of the hinds number. Applying the simulation of the model population meeting the parameters indicated in the inventory, the researchers calculated and proposed the optimal indicators of harvesting individual age and sex groups. The proposed model of hunting monitoring and management assumes optimization of environmental conditions, structure and size of the actual population within the next 10 years.

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Assessment of a daily defecation rate of fallow deer upon a closed population study

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun201260060173 ◽

2012 ◽

Vol 60 (6) ◽

pp. 173-180 ◽

Cited By ~ 2

Author(s):

Antonín Košnář ◽

Romana Rajnyšová

Keyword(s):

Population Density ◽

Fallow Deer ◽

Early Spring ◽

Summer Season ◽

Accurate Assessment ◽

Indirect Methods ◽

Defecation Rate ◽

Closed Population ◽

Deer Population ◽

Precise Knowledge

Many indirect methods of counting even-toed ungulates are based on the principle of accumulating dung in a known area per a unit of time. In order to provide the most accurate assessment of the population size, these methods require the knowledge of daily defecation of the monitored species. The main objective of the study submitted is the assessment of a daily defecation rate of fallow deer based on the monitoring of its closed population. A partial objective is the assessment of the distribution of fallow deer in an enclosed area with a view to biotopes represented. A fallow deer population was studied for the period of three years (2009–2011) in a fenced-in area (8 ha). During this period, dung heaps were counted in forty sites with the total area of 0.8 ha in all seasons of the year. In each season, the sites were cleared, and the dung was counted after a seven-day exposure. This counting was performed twice in each season. Thanks to the precise knowledge of the number of monitored animals, daily defecation rates (DDR) were derived upon the dung found, using a formula for the calculation of population density. Subsequently, the determined DDRs were verified by direct observation. The highest average DDR value calculated from the formula (21.11 ± 0.32 S.E.) was obtained in the summer season. The lowest defecation of fallow deer was established to be in winter (12.34 ± 0.25 S.E.) and early spring (10.61 ± 0.24 S.E.).

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Is deer herbivory directly proportional to deer population density? Comparison of deer feeding frequencies among six forests with different deer density

Forest Ecology and Management ◽

10.1016/j.foreco.2011.04.009 ◽

2011 ◽

Vol 262 (3) ◽

pp. 432-439 ◽

Cited By ~ 12

Author(s):

Ryosuke Koda ◽

Noboru Fujita

Keyword(s):

Population Density ◽

Deer Population ◽

Deer Herbivory ◽

Deer Density

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Reduced Tillage Increases Population Density of Soil Macrofauna in a Semiarid Environment in Central Queensland

Environmental Entomology ◽

10.1093/ee/28.2.163 ◽

1999 ◽

Vol 28 (2) ◽

pp. 163-172 ◽

Cited By ~ 22

Author(s):

Alexandra C. Wilson-Rummenie ◽

Bruce J. Radford ◽

Les N. Robertson ◽

Gordon B. Simpson ◽

Kerry L. Bell

Keyword(s):

Population Density ◽

Reduced Tillage ◽

Soil Macrofauna ◽

Semiarid Environment

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Factors Affecting Sockeye Salmon (Oncorhynchus nerka) Growth in Four Lakes of the Fraser River System

Journal of the Fisheries Research Board of Canada ◽

10.1139/f74-106 ◽

1974 ◽

Vol 31 (5) ◽

pp. 871-892 ◽

Cited By ~ 30

Author(s):

J. C. Goodlad ◽

T. W. Gjernes ◽

E. L. Brannon

Keyword(s):

Population Density ◽

Standing Crop ◽

Sockeye Salmon ◽

River System ◽

Growing Season ◽

High Elevation ◽

Zooplankton Abundance ◽

Fraser River ◽

Factors Affecting ◽

Short Growing Season

Analysis of data from four sockeye rearing lakes of the Fraser River system for periods of up to 20 yr provided information on the relation of estimated fish density (female spawners/ha), temperature, and zooplankton standing crops to growth. The lakes differed widely in all attributes. Growth was inversely related to estimated population density in three of the lakes, but wide variations in growth at low density occurred in the fourth, a cold lake at high elevation with short growing season. In this lake, and to a lesser extent in another lake with short growing season, temperature during fry emergence and early lake residence accounted for much of the recorded fluctuation in growth. Reduced zooplankton abundance was associated with high sockeye density in two of the lakes with intermediate standing crops and greatest sockeye densities, but was not recorded in a lake of low standing crop and intermediate sockeye density. Sockeye feeding was found to be highly selective in one lake, and a limited proportion of the zooplankton standing crop was utilized. It is suggested that reduction in standing crop by grazing of juvenile sockeye, and associated decrease in growth, is greatest as the large zooplankters are progressively reduced in abundance. Further reduction in standing crop and in sockeye growth was suggested to proceed at a slower rate. Competition at high population density was concluded to be the factor most responsible for reducing sockeye growth.

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Spatial Estimation of Sika Deer Population Density Distribution

Journal of Forest Planning ◽

10.20659/jfp.13.1_1 ◽

2007 ◽

Vol 13 (1) ◽

pp. 1-14 ◽

Cited By ~ 1

Author(s):

Hiroshi Kondoh ◽

Koichi Ikeda ◽

Toru Koizumi

Keyword(s):

Population Density ◽

Density Distribution ◽

Sika Deer ◽

Spatial Estimation ◽

Deer Population

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Browsing Patterns of White-Tailed Deer Following Increased Timber Harvest and a Decline in Population Density

International Journal of Forestry Research ◽

10.1155/2010/592034 ◽

2010 ◽

Vol 2010 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Shawn M. Crimmins ◽

John W. Edwards ◽

W. Mark Ford ◽

Patrick D. Keyser ◽

James M. Crum

Keyword(s):

Population Density ◽

Odocoileus Virginianus ◽

Population Control ◽

Timber Harvest ◽

Population Densities ◽

Growth And Survival ◽

Deer Population ◽

Mature Forest ◽

Central Appalachians ◽

A Site

We examined browsing patterns of white-tailed deer (Odocoileus virginianus) on a site in the central Appalachians that experienced a substantial (>50%) reduction in deer population density and an increase in the amount of timber harvest since 2001. We sampled woody browse in and immediately adjacent to 12 clearcuts ranging in age from 0–5 years postharvest in summer 2007. Clearcut-interior areas had higher woody browse abundance and browsing rates than clearcut-edge or mature forest areas. Woody browse abundance was slightly higher within individual clearcuts than in 2001 at higher population densities and lower timber harvest rates. Overall browsing rates declined from approximately 17% in 2001 to less than 5% during our study, suggesting that the combination of deer population control, and increasing the amount of timber harvest across the landscape can reduce herbivory to levels that may not impede growth and survival of forest vegetation.

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Wildlife and forest management measures significantly impact red deer population density

Šumarski list ◽

10.31298/sl.141.3-4.4 ◽

2017 ◽

Vol 141 (3-4) ◽

pp. 149-150 ◽

Cited By ~ 1

Author(s):

Matija Stergar ◽

Klemen Jerina

Keyword(s):

Forest Management ◽

Population Density ◽

Cervus Elaphus ◽

Red Deer ◽

Deer Population ◽

Management Measures

Jelen obični (Cervus elaphus L.) je u mnogim dijelovima svijeta važna ekološka vrsta i popularna divljač, te kao takva ima značajan izravan utjecaj na čovjeka. Istovremeno može imati štetne posljedice na okoliš, posebice na šumarstvo. Težina ovih posljedica ovisi o gustoći populacija jelena običnog, što zauzvrat u značajnom stupnju ovisi o kvaliteti staništa i prijašnjem upravljanju ovom vrstom. Oba čimbenika snažno odražavaju ljudske utjecaje. Ovo istraživanje proučava utjecaje određenih okolišnih i povijesnih čimbenika, posebice onih antropogenih, na raširenost i lokalne gustoće populacija jelena običnog. Područje istraživanja je Slovenija, zemljopisno, klimatski i krajobrazno izuzetno raznovrsna država. Jelen obični je u povijesti istrijebljen i reintroduciran prije 100 godina na nekoliko mjesta, a također je i spontano imigrirao iz Mađarske (Slika 1). Danas je proširen na 60% površine države, ali nije još dosegao sva pogodna staništa zbog sporog širenja. Analiza je obuhvatila nezavisne varijable širokog raspona okolišnih varijabli i varijable “troškovna udaljenost”, koja prikazuje “težinu” disperzije jelena običnog od mjesta reintrodukcije, odnosno imigracije. Procjene lokalnih gustoća jelena običnog (zavisna varijabla) su dobivene pomoću dvije metode: podaci o izvršenim odstrjelnim kvotama i metodom brojanja izmeta. Vrijednosti varijabli su pripremljene na relativno finoj prostornoj rezoluciji (imajući na umu površinu cijelog područja) od 1 km2. U skladu s teorijom o višestrukom izboru staništa, zavisnost jelena običnog o okolišu je analizirana na dvije razine: 1) globalni doseg jelena običnog (nazočnost/nenazočnost) i 2) gustoće lokalnih populacija unutar područja raširenosti. Na obje razine je provedena bivarijatna (korelacija) i multivarijatna (regresija) analiza. Nazočnost jelena običnog je najvjerojatnija u blizini mjesta reintrodukcije, odnosno imigracije, što ističe važnost varijable “troškovna udaljenost”, te u velikim šumskim kompleksima, što ukazuje na pozitivan utjecaj udjela šume i veličinu šumske plohe te negativan utjecaj gustoće ruba šume (Tablica 1, Tablica 2). Ove varijable također utječu na gustoću populacije, koja raste s padom udaljenosti od hranilišta i pozitivno je vezana s udjelom sastojina u kojima dominira obična smreka. Korelacija također ukazuje na pozitivnu ovisnost s udjelom mladih sastojina (Tablica 1, Tablica 3). Troškovna udaljenost od mjesta reintrodukcije te udio i kontinuitet šume prikazuje ljudske intervencije u povijesti (nekadašnje upravljanje jelenom običnim i korištenje prostora od strane čovjeka). Poznavanje utjecaja ovih čimbenika na jelena običnog je stoga važno za razumijevanje prošlosti i predviđanje buduće dinamike populacije. Stanište jelena običnog u Sloveniji još uvijek nije u potpunosti nastanjeno i širenje se nastavlja. Stoga se očekuje kontinuirano širenje jelena običnog, imajući na umu da brzina ovisi o načinima upravljanja prostorom. Stanje je slično i u većini drugih europskih zemalja. Još je važnije poznavati utjecaje mjera u današnjem lovstvu i šumarstvu koje, mogu biti prilagođene s ciljem postizanja željenih utjecaja. Neke ustaljene prakse upravljanja često ostvaruju utjecaje suprotne željenima,i u budućnosti bi trebale biti ponovno razmatrane. U budućnosti bi više pozornosti trebalo posvetiti izboru mjesta na kojem bi se postavila hranilišta za jelensku divljač, a na nekim područjima bi se intenzitet prihranjivanja jelenske divljači trebao reducirati. Udio mladih stabala u šumama Slovenije je prenizak; stoga bi ili trebalo proširiti područja obnove šumskih sastojina ili osnovati krmne površine za divljač (remize). Upravljanje odnosima između šume i divljači zahtjeva suradnju djelatnika u lovstvu i djelatnika u šumarstvu. Metoda primijenjena u našem istraživanju također bi mogla biti korištena za poboljšanje bonitiranja lovišta za jelensku divljač, jer su procjene utjecaja pojedinih okolišnih čimbenika na kvalitetu staništa jelena običnog temeljene na kvantitativnoj analizi.

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