DOCUMENTATION STANDARDS FOR WILDLIFE SOUND RECORDINGS

ABSTRACT

Shearwaters are nocturnal seabirds that rely on olfaction and acoustics to communicate at night. Although previous studies have described the vocal repertoire of some shearwater species, there is a need for more precise experimental data investigating the biological relevance of these acoustic signals in this seabird group. The present paper focuses on the vocal behaviour of the Yelkouan shearwater Puffinus yelkouan, a poorly studied species which produces a single major call composed of two notes, a noisy note and a clear one. A quantitative analysis of the calls allowed to extract the acoustic parameters supporting both sexual and individual signatures. Playback experiments were conducted during the incubation period to test the ability of the Yelkouan shearwater (1) to vocally identify the sex of the emitter, and (2) to discriminate the mate from a non-mate. We showed that birds discriminate the sex of the emitter, calling back almost exclusively to calls of birds of the same sex. Among the few birds replying to calls of the opposite sex, females responded to calls of their partner only, whereas males responded equally to calls of the partner or to calls of a non-partner, suggesting that females are vocally more selective than males.     

FRIENDS OF WILDLIFE SOUND AT NSA

ABSTRACT

The problem of categorization arises in any classification system because classes should be discrete while the characteristics of most natural objects and aspects of nature are more or less gradual. In systematics, this problem usually is solved by creating several levels of categories, such as class, order, family, genus and species. In the existing killer whale discrete call classification, only two levels occur—call type and call subtype. In this paper we describe structural categories at a broader level than call type in the discrete sounds of killer whales and compare these categories between and within vocal clans in a community of resident killer whales from Southeast Kamchatka, Russian Far East, and also with killer whales outside this community. We found four main classes of discrete calls in the repertoire of resident killer whales from Southeast Kamchatka. The calls of Southeast Kamchatka transient killer whales and Sakhalin killer whales do not fall into these classes. This suggests that the resident killer whale community from Southeast Kamchatka has some rules defining the structure of calls which are typical for this community. Consequently, all resident killer whales from Southeast Kamchatka can be said to share the same vocal tradition.     

USE OF MINERALISED WATER BY KALAHARI WILDLIFE AND ITS EFFECTS ON HABITATS

This study surveyed the use made by springbok, hartebeest, wildebeest and gemsbok, in particular, of mineralised artificial waterholes along the Nossob river in the southern Kalahari and the effects of this use on the delicate surrounding habitats, as a basis for evaluating the uses and limitations of such water in the management of these species. Taking into account the chemical composition of the dissolved salts in the water; the status of the vegetation and conservation trends near water holes; the relative use made of the waterholes by the antelopes; and land use history, it was concluded that: (a) the animals made regular use of the water, some of which was more mineralised than that recommended for domestic stock, including sheep; (b) there was no relationship between the total dissolved salts and animal use, although there may have been some association between gemsbok use and certain ions; (c) wildlife attracted to boreholes had very little effect on the stability of some surrounding habitats, but may have retarded recovery in areas downgraded by past land use, and (d) under these circumstances the effects of this land use were still amply evident after 2¹/₂ decades. From this and other evidence, it is suggested that, at the present level of knowledge, mobile wildebeest populations can be stabilised by the provision of relatively potable water, and mineralised water may be used to raise the levels of springbok, hartebeest and gemsbok populations. However, as the water is less of a limiting factor than for species requiring regular drinking water, the increase in density may be relatively limited and so less of a danger to the maintenance of surrounding habitats.     

13C NMR在马利筋族植物C21甾类成分结构研究中的应用

本文介绍了＾１３ＣＮＭＲ在以列筋族植物Ｃ２１甾类成分甙元类型工基的确定、糖的种类、连接顺序的判断等方面的应用。     

SOUND PRODUCTION AND SOUND EMISSION IN SEVEN SPECIES OF EUROPEAN TETTIGONIIDS PART III. DETERMINATION OF THE MECHANISM OF SOUND PRODUCTION USING CEPSTRUM ANALYSIS

ABSTRACT

The mechanism of sound production in tettigoniids is examined by applying the method of ‘cepstrum’ analysis to insect calls. The power cepstrum is defined as the inverse Fourier transform of the logarithmic power spectrum. This analysis shows that the tettigoniid sound signal is a convolution in time of probably two components. The first is caused by the initial impact of teeth of the stridulatory file on the left wing against the plectrum on the right wing (termed the input pulse); the second is caused by the oscillating properties of the tegmina (these being a function of the intrinsic frequencies of dorsal fields and mirror and their damping properties). In the cepstrum each component appears as a varying number of peaks. The tooth impacts cause a very low quefrency peak probably representing the time in which the two tegmina are in contact during each impact and high quefrency peaks representing the impulse repetition rate. The oscillating properties of the tegmina cause two major quefrency peaks which can be clearly related to the size of the dorsal fields and of the mirror respectively, and therefore to their intrinsic frequencies. The high damping factor of the tegmina together with the transient shape of the tegminal input pulse causes a strong time limitation of the impulses and is therefore responsible for the broad frequency bands occurring in the power spectra of the tettigoniid songs. The impulse generation of a synthetic tettigoniid song is discussed.