Estimating density, population size and dynamics of Common Buzzard (Buteo buteo) in the West Carpathian region by a new method

2009 ◽  
Vol 3 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Karol Šotnár ◽  
Ján Topercer

Estimating density, population size and dynamics of Common Buzzard (Buteo buteo) in the West Carpathian region by a new method In the Hornr Ponitrie Region (central Slovakia) during 1991-2001 we conducted a regular survey of Common Buzzard nests. In 2002-2006 our sampling effort increased and within the selected areas we studied buzzard dispersion/distribution, density and population dynamics using a new method of large-scale thorough search for nests with multiple nest check. The method is designed to estimate the dispersion/distribution, density and population size of target species (particularly raptors) at an absolute scale of abundance in large tracts of heterogeneous landscapes for studies of population fluctuations, trophic dynamics, reproductive success, habitat selection and use. It consists of systematic search for nests with extent of several tens of km2 and grain of c. 3000 m2, identifying and positioning the nests, and subsequent 1-3 nest checks during the each of three or more consecutive breeding periods. Further essential features include correct record of nest positions and other variables, combination of nest checks with ringing and marking, proportional sampling in apparently suitable and less suitable areas and proper timing and spacing of nest visits. In 2007 the sampling focused on DSF (Databank of Slovak Fauna) grid square 7377 covering c. 135 km2. We searched 71 km2 in total and estimated the density at 129 pairs/100 km2. Within the district of Prievidza (959 km2) we found 150 active buzzard nests. In 2008 we sampled the grid square 7377 more extensively, including higher altitudes (800-1200 m a. s. l.). Sampling of 82 km2 in total yielded the density estimate of 93 pairs/100 km2. Within the district of Prievidza we found 110 active buzzard nests. The reproductive success over four year period averaged 1.2 fledgling per active nest (n = 310 nests). Our sample enabled us to estimate the minimum population size in the whole grid square 7377 at 130 breeding pairs, i.e. 96 pairs/100 km2. Minimum population size for the whole district of Prievidza can be estimated approximately at 500 breeding pairs (52 pairs/100 km2), c. 350 of which breed in mountain forests, c. 80 in agricultural woodlots, and c. 70 in riparian vegetation. Rough estimate of minimum breeding population in the whole Slovakia is c. 15 000 pairs, i.e. on average 31 pairs/100 km2.

1968 ◽  
Vol 16 (1) ◽  
pp. 27 ◽  
Author(s):  
JL Readshaw

Banding records were used to estimate the size of non-breeding winter flocks of the pied currawong, Strepera graculina, at Albury, N.S.W., during 1964 and 1965. A new method of analysing mark-recapture data is compared with conventional methods, and it is shown that the flocks contained between 500 and 1000 birds in both years. In 1964, the new method provided information on emigration and immigration that was not apparent when the data were treated in the conventional way. The new approach considers the common situation in which a population (flock) is sampled continuously by catching one member (bird) at a time, marking (banding) it, and returning it to the population. For closed populations, the population size was estimated by a method involving cumulative catch and recapture data. Subsequently, this method was successfully tested by simulating the sampling of 20 "populations" of 10,000 random numbers with a computer. The method also provided a simple way of controlling sampling effort based on recapture data to obtain any desired precision in the estimation of population size.


2018 ◽  
Vol 45 (1) ◽  
pp. 80-91 ◽  
Author(s):  
T. R. Birkhead ◽  
I. Charmantier ◽  
P. J. Smith ◽  
R. Montgomerie

The European Honey-buzzard (Pernis apivorus) was first accurately described and clearly distinguished from the Common Buzzard (Buteo buteo) by Francis Willughby and John Ray in their Ornithology, originally published in Latin in 1676. Alfred Newton's statement that Pierre Belon had described the species over a century earlier is not entirely correct, as Belon confused this honey-buzzard's features with those of the common buzzard and even appeared uncertain whether it was a separate species. One of Willughby's important contributions to ornithology was the identification and use of “characteristic marks” to distinguish and identify species, including those that distinguish the European Honey-buzzard from the Common Buzzard. Because Willughby provided the first accurate description of Pernis apivorus  – and because his contribution to ornithology has never been formally recognized –  we propose that the common name of the European Honey-buzzard be changed to Willughby's Buzzard.


Author(s):  
Adrian Mestecăneanu ◽  
Florin Mestecăneanu

Observations regarding the flight biology and behaviour of the Common buzzard (Buteo Buteo) in the Râul Doamnei hydrographical basin (Romania) In this paper, the authors analyse the flight biology and behaviour of the Common buzzard (Buteo buteo) observed in the Râul Doamnei hydrographical basin, depending on the environmental conditions and ecological seasons. Along three years, during the 3031 observations, 4549 individuals were observed.


Author(s):  
Deep K. Datta-Ray

The history of Indian diplomacy conceptualises diplomacy racially—as invented by the West—and restrictively—to offence. This is ‘analytic-violence’ and it explains the berating of Indians for mimicking diplomacy incorrectly or unthinkingly, and the deleting, dismissing, or denigrating, of diplomatic practices contradicting history’s conception. To relieve history from these offences, a new method is presented, ‘Producer-Centred Research’ (PCR). Initiating with abduction, an insight into a problem—in this case Indian diplomacy’s compromised historicisation—PCR solves it by converting history’s racist rationality into ‘rationalities’. The plurality renders rationality one of many, permitting PCR’s searching for rationalities not as a function of rationality but robust practices explicable in producer’s terms. Doing so is exegesis. It reveals India’s nuclear diplomacy as unique, for being organised by defence, not offence. Moreover, offence’s premise of security as exceeding opponent’s hostility renders it chimerical for such a security is, paradoxically, reliant on expanding arsenals. Additionally, doing so is a response to opponents. This fragments sovereignty and abdicates control for one is dependent on opponent’s choices. Defence, however, does not instigate opponents and so really delivers security by minimising arsenals since offence is eschewed. Doing so is not a response to opponents and so maintains sovereignty and retains control by denying others the right to offense. The cost of defence is courage, for instance, choosing to live in the shadow of nuclear annihilation. Exegesis discloses Balakot as a shift from defence to offence, so to relieve the Bharatiya Janata Party’s (BJP) leadership of having to be courageous. The intensity of the intention to discard courage is apparent in the price the BJP paid. This included equating India with Pakistan, permitting it to escalate the conflict, and so imperiling all humanity in a manner beyond history.


2016 ◽  
Vol 144 (4) ◽  
pp. 1571-1589 ◽  
Author(s):  
Rory G. J. Fitzpatrick ◽  
Caroline L. Bain ◽  
Peter Knippertz ◽  
John H. Marsham ◽  
Douglas J. Parker

Abstract Accurate prediction of the commencement of local rainfall over West Africa can provide vital information for local stakeholders and regional planners. However, in comparison with analysis of the regional onset of the West African monsoon, the spatial variability of the local monsoon onset has not been extensively explored. One of the main reasons behind the lack of local onset forecast analysis is the spatial noisiness of local rainfall. A new method that evaluates the spatial scale at which local onsets are coherent across West Africa is presented. This new method can be thought of as analogous to a regional signal against local noise analysis of onset. This method highlights regions where local onsets exhibit a quantifiable degree of spatial consistency (denoted local onset regions or LORs). It is found that local onsets exhibit a useful amount of spatial agreement, with LORs apparent across the entire studied domain; this is in contrast to previously found results. Identifying local onset regions and understanding their variability can provide important insight into the spatial limit of monsoon predictability. While local onset regions can be found over West Africa, their size is much smaller than the scale found for seasonal rainfall homogeneity. A potential use of local onset regions is presented that shows the link between the annual intertropical front progression and local agronomic onset.


Oryx ◽  
2011 ◽  
Vol 45 (1) ◽  
pp. 112-118 ◽  
Author(s):  
Özgün Emre Can ◽  
İrfan Kandemi̇r ◽  
İnci̇ Togan

AbstractThe wildcat Felis silvestris is a protected species in Turkey but the lack of information on its status is an obstacle to conservation initiatives. To assess the status of the species we interviewed local forestry and wildlife personnel and conducted field surveys in selected sites in northern, eastern and western Turkey during 2000–2007. In January–May 2006 we surveyed for the wildcat using 16 passive infrared-trigged camera traps in Yaylacı k Research Forest, a 50-km2 forest patch in Yenice Forest in northern Turkey. A total sampling effort of 1,200 camera trap days over 40 km2 yielded photo-captures of eight individual wildcats over five sampling occasions. Using the software MARK to estimate population size the closed capture–recapture model M0, which assumes a constant capture probability among all occasions and individuals, best fitted the capture history data. The wildcat population size in Yaylacı k Research Forest was estimated to be 11 (confidence interval 9–23). Yenice Forest is probably one of the most important areas for the long-term conservation of the wildcat as it is the largest intact forest habitat in Turkey with little human presence, and without human settlements, and with a high diversity of prey species. However, it has been a major logging area and is not protected. The future of Yenice Forest and its wildcat population could be secured by granting this region a protection status and enforcing environmental legislation.


1963 ◽  
Vol 20 (1) ◽  
pp. 59-88 ◽  
Author(s):  
J. E. Paloheimo

Techniques of estimating population size, level of fishing, and the degree of dependence of fishing success on environmental factors are examined on the basis of tagging, catch and effort data. A new method is developed to estimate population size from catch, effort, and temperature data when the catchability varies with temperature.The methods of estimation discussed are applied to data collected from a number of lobster fisheries on Canada's Atlantic coast. Analysis confirms a relationship between the catchability of lobsters and bottom temperature. Differences in this relationship are found between areas and between tagged and untagged lobsters within areas. It is suggested that these differences are attributable to the differences in densities as well as to aggregations of lobsters and fishing. The effect of these aggregations on population size estimates is considered.Calculated average catchabilities at comparable temperatures are different for different areas. These differences are correlated with the numbers of trap hauls per day per square miles fished. It is suggested that the differences in the catchabilities might be due to interactions between units of gear not predicted by the customary relationship between catch and effort.


Sign in / Sign up

Export Citation Format

Share Document