A DNA test to sex most birds.

Images of outdoor scenes captured in bad weather suffer from poor contrast. Under bad weather conditions, the light reaching a camera is severely scattered by the atmosphere. The resulting decay in contrast varies across the scene and is exponential in the depths of scene points. Therefore, traditional space invariant image processing techniques are not sufficient to remove weather effects from images. We present a physics-based model that describes the appearances of scenes in uniform bad weather conditions. Changes in intensities of scene points under different weather conditions provide simple constraints to detect depth discontinuities in the scene and also to compute scene structure. Then, a fast algorithm to restore scene contrast is presented. In contrast to previous techniques, our weather removal algorithm does not require any a priori scene structure, distributions of scene reflectances, or detailed knowledge about the particular weather condition. All the methods described in this paper are effective under a wide range of weather conditions including haze, mist, fog, and conditions arising due to other aerosols. Further, our methods can be applied to gray scale, RGB color, multispectral and even IR images. We also extend our techniques to restore contrast of scenes with moving objects, captured using a video camera.

/pdf/contrast-restoration-of-weather-degraded-images-orn61jh9qu.pdf

Contrast restoration of weather degraded images

Monitoring programmes are being used increasingly to assess spatial and temporal trends of biological diversity, with an emphasis on evaluating the efficiency of management policies. Recent reviews of the existing programmes, with a focus on their design in particular, have highlighted the main weaknesses: the lack of well-articulated objectives and the neglect of different sources of error in the estimation of biological diversity. We review recent developments in methods and designs that aim to integrate sources of error to provide unbiased estimates of change in biological diversity and to suggest the potential causes.

Monitoring of biological diversity in space and time

https://crrc.unh.edu/sites/crrc.unh.edu/files/ei_1485.pdf

From comparative risk assessment to multi-criteria decision analysis and adaptive management: recent developments and applications.

Introduced rats are now being eradicated from many islands. Increasingly, these eradications are contested by activists claiming moral, legal, cultural, historic or scientific reasons and poorly documented evidence of effects. We reviewed the global literature on the effects of rats on island flora and fauna. We then used New Zealand as a case study because of its four-decade history of rat eradications and many detailed and innovative studies of how rats affect native species. These include use of exclosures, local manipulations of rat populations, video surveillance, and measurements of responses following eradications. The most intensive studies have been on the Pacific rat (Rattus exulans), a small South-East Asian species spread by Polynesians throughout the Pacific. These and the more recently introduced Norway rat (R. norvegicus) and ship (roof) rat (R. rattus) suppress some forest plants, and are associated with extinctions or declines of flightless invertebrates, ground-dwelling reptiles, land birds, and burrowing seabirds. On islands off France, Norway rats are also implicated in declines of shrews. Globally, ship rats were associated with declines or extinctions of the largest number of indigenous vertebrate species (60), including small mammals such as deer mice and bats. Effects of rats on forest trees and seabird populations are sufficiently pervasive to affect ecosystem structure and function. However, the data are patchy. Deficiencies in our knowledge would be reduced by documenting distribution and abundance of indigenous species before and after eradications. Comprehensive measurements of the responses of indigenous species to rat eradications would enable the development of testable models of rat invasion effects.

Have the Harmful Effects of Introduced Rats on Islands been Exaggerated

Successful recovery of North Island kokako Callaeas cinerea wilsoni populations, by adaptive management

Recovery and maintenance of North Island kokako (Callaeas cinerea wilsoni) populations through pulsed pest control

https://www.nrm.se/download/18.4e1d3ca810c24ddc7038000945/Ewen+et+al+Stitchbird+MPEV+2006.pdf

Systematic affinities of two enigmatic New Zealand passerines of high conservation priority, the hihi or stitchbird Notiomystis cincta and the kokako Callaeas cinerea.

Demography of two landsnail populations (Placostylus ambagiosus, Pulmonata: Bulimulidae) in relation to predator control in the far north of New Zealand

North Island kokako (Callaeas cinerea wilsoni) appear sexually monomorphic. Females are, on average, slightly smaller than males in most body measurements. Mean tarsus length was significantly smaller among females at all sites and can be used to predict sex of unknown birds with up to 86% accuracy. A simple discriminant function, using tarsus and wing chord measurements, was derived which increased sex resolution to over 90% at some sites. This is sufficient accuracy to provide a useful field technique for kokako research and conservation management. Best discri- minant functions for different sites are presented and their geographical limitations are discussed.

https://notornis.osnz.org.nz/system/files/Notornis_48_4_217.pdf

Ian Flux

Papers

Successful recovery of North Island kokako Callaeas cinerea wilsoni populations, by adaptive management

Recovery and maintenance of North Island kokako (Callaeas cinerea wilsoni) populations through pulsed pest control

Systematic affinities of two enigmatic New Zealand passerines of high conservation priority, the hihi or stitchbird Notiomystis cincta and the kokako Callaeas cinerea.

Demography of two landsnail populations (Placostylus ambagiosus, Pulmonata: Bulimulidae) in relation to predator control in the far north of New Zealand

A field technique for determining the sex of North Island kokako (Callaeas cinerea wilsonl)