geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Survey area covered by the point count method


, : Survey area covered by the point count method. Dansk Ornitologisk Forenings Tidsskrift 78(1-2): 25-28

When applying the point count method in biological monitoring programs it is essential to know the registration distance, it is essential to know the registration distance, i.e., the covered area around each point. Registration distances are calculated by comparing results from the Point Count Method with bird densities obtained by mapping in the same area. The research area, Vaserne in Zealand [Denmark], consists of 69% Alnus/Salix marsh, 13% meadow, 10% lake, 5% deciduous forest and 3% suburbs. The field work was carried out from mid-May to mid-June 1980 and included 10 mapping surveys and 3 point counts. Territory maps were made for passerine birds. An effective registration distance is obtained as follows: the stationary male population S around each point is calculated from the recorded males R, the proportion of stationary males to total males (S/T), and the registration efficiency e (formulae (1) and (2)). The point count is considered to cover a circular area around each point containing the same number of mapped stationary males. The registration distance r is defined as the radius of this circle. Registration efficiencies were obtained from Enemar (1959). The available data allowed specific treatment of 5 spp. The remaining species are included in a combined registration distance; although the usefulness of this value may be limited it provides an order of magnitude until specific values are available. The registration distance generally seems to be .apprx. 90 m in tree-covered areas and 150 m in open country. The factor k for converting point count records into total population densities (males/km2) is estimated for the 5 spp. and for all 17 spp. [Parus major, P. caeruleus, Luscinia luscinia, Troglodyles troglodytes, Erithacus rubecula, Turdus merula, Acrocephalus scirpaceus, A. palustris, Sylvia atricapilla, S. borin, S. communis, Phylloscopus collybita, Prunella modularis, Sturnus vulgaries, Fringilla coelebs, Emberiza schoeniclus and Phylloscopus trochilus] combined. This factor varies considerably between species and the justification of a common value is questionable. The specific values appear accurate to a factor of .apprx. 0.7 which represents a considerable improvement from previous estimates (Klug-Andersen et al., 1983).

US$29.90


Other references

Shcherbakova, Sp, 1984: Field germination rate and germination intensity of peach and almond seeds. Biulleten' Gosudarstvennogo Nikitskogo botanicheskii sada4(54): 45-49

Egley G.H.; Paul R.N.Jr, 1981: Morphological observations on the early imbibition of water by sida spinosa malvaceae seed. The chalazal area is confirmed as the site of initial water entry into prickly sida (S. spinosa L.) seeds. Very early during imbibition of water, a kidney-shaped area of the seed coat separates from underlying cells forming a blister. The blister...

Nunes, F.P.; Bishop, T.; Prasad, M.L.; Madison, J.Mark.; Kim, D.Y., 2008: Laryngeal candidiasis mimicking malignancy. Isolated laryngeal candidiasis in immunocompetent individuals is a rare entity with fewer than 40 cases reported in the literature. Laryngeal candidiasis secondary to inhaled steroid therapy is usually mild and has been reported in 10% to 15% of p...

Hoffling, J., 1993: Cow planning programs tested. In cattle farming, the focus of management is claimed to lie in herd control, performance assessment and correct feeding. The DLG (German Agricultural Society) advisory group tested 7 cow planning computer programs using herd management, different...

Shimkus, J., 1997: Spreading the word: grass-roots infection education. Health Facilities Management 10(12): 33-34

Dubas F.; Leonard R.B.; Hanlon R.T., 1986: Chromatophore motoneurons in the brain of the squid lolliguncula brevis a horseradish peroxidase study. The location of the motoneuron somata controlling activity of the chromatophore muscles was studied in the squid Lolliguncula brevis. Retrograde transport of horseradish peroxidase from injection sites in the skin or in the mantle muscle establish...

Vatteroni, M., 1966: Present possibilities in the prevention of perinatal mortality. Minerva Pediatrica 18(2): 70-73

Gay, R.D.; Dawson, S.J.; Latchman, D.S., 1997: The different inhibitory domains of the Oct-2 transcription factor have distinct functional activities. The Oct-2 POU family transcription factor contains three distinct regions whose deletion reduces its ability to inhibit transcription via its octamer binding site. Here we show that only one of these inhibitory domains is capable of also inhibitin...

Dokal, I.; Chase, A.; Morgan, N.V.; Coulthard, S.; Hall, G.; Mathew, C.G.; Roberts, I., 1996: Positive diepoxybutane test in only one of two brothers found to be compound heterozygotes for Fanconi's anaemia complementation group C mutations. Fanconi's anaemia (FA) is an autosomal recessive disorder characterized by diverse congenital abnormalities, the development of progressive bone marrow failure, and an increased predisposition to malignancy, particularly acute leukaemia. The...

Perlow, M.J.; Kumakura, K.; Guidotti, A., 1980: Prolonged survival of bovine adrenal chromaffin cells in rat cerebral ventricles. Dispersed, cultured bovine adrenal chromaffin cells transplanted into the cerebral ventricles of neonatal and adult rats survived at least 2 mo without evidence of immunological rejection. The cells can be identified by their strong yellow fluores...