CHARACTERISTICS OF TERRITORIAL AND MATING CALLS IN WILLOW PTARMIGAN LAGOPUS L. LAGOPUS

ABSTRACT

During territorial behaviour and pair formation willow ptarmigan cocks and hens use several different calls. Cocks use mainly a “flight call”, a “ground call” and three different “threat calls”. Hens give similar calls to cocks. It is suggested that the structure of the calls is well adapted to (1) transmit their possible information content over long distances, and (2) make localization easier for birds during the territorial display periods, which take place mainly in poor light at dusk and dawn. We also suggest that the cock and hen calls express different degrees of aggressiveness, and that hen calls, in addition to attracting cocks, function as territorial “keep out” signals to other hens.     

AUTOMATIC FEATURE EXTRACTION AND CLASSIFICATION OF CROSSBILL (LOXIA SPP.) FLIGHT CALLS

ABSTRACT

In this paper a new method for the automatic classification of bird sounds is presented. Our method is based on acoustic parameters (features) taken from the first harmonic component computed from the sound spectrogram. The features are based on a line segment approximation of the first harmonic component. The final feature vectors, consisting of 16 real numbers, are then classified using a self-organizing map (SOM) neural network. Flight calls of four crossbill species (Loxia spp.) are used as a test example. In the first phase, an unsupervised network was trained and tested using common crossbill L. curvirostra flight calls recorded mainly in the Netherlands. The network was tested using two-barred L. leucoptera, Scottish L. scotica and parrot L. pytyopsittacus crossbill flight calls in the second phase. Finally, the results were validated applying the same network to flight calls of common crossbills and parrot crossbills recorded in Finland. The method automatically separated common crossbill flight calls from those of parrot crossbills. The classification accuracy of the Dutch recordings was 58% in the first phase and 54% in the second phase. The Finnish recordings were classified with 54% accuracy.     

PCR-based,rapid diagnosis of parasitism of Lygus spp. (Hemiptera: Miridae) by Peristenus relictus (Hymenoptera: Braconidae)

Several species of Lygus (Heteroptera: Miridae: Mirini) are serious crop pests in North America where their parasitism rate by native nymphal parasitoids is generally lower than in Europe. Peristenus relictus (Ruthe) (formerly P. stygicus Loan) (Hymenoptera: Braconidae: Euphorinae) is the predominant nymphal parasitoid of several Lygus spp. in the warm Mediterranean region and has been a candidate for introduction against Lygus hesperus Knight and L. lineolaris (Palisot de Beauvois) in the southern US. We report a rapid, sensitive, and specific PCR-based assay for diagnosis of P. relictus immature stages within Lygus nymphs that entails three steps: DNA extraction, PCR of the partial mitochondrial COI gene, and agarose gel electrophoresis. The PCR-based methodology is species-specific because the target DNA of other sympatric, congeneric species was not amplified with use of the primers developed for P. relictus diagnosis. The sensitivity of the PCR method, assessed through spike tests, was established by the detection of a ratio of 1:10,000 P. relictus DNA to Lygus DNA. Molecular diagnosis of parasitism of field collected nymphs is achievable in one day, eliminating the need to rear nymphs to obtain adult parasitoids for morphological identification.     

Notes on New Zealand mammals 4. Animal road‐kill “blackspots”

Abstract

Repeated counts of road‐killed animals have revealed sites where possums (Trichosurus vulpecula), rabbits (Oryctolagus cuniculus), hedgehogs (Erinaceus europaeus), gulls (Larus dominicanus, L. novaehollandiae) and shags (Phalacrocorax carbo) were killed in unusual numbers. These “blackspots” were not correlated with the volume of traffic, but were mapped at or near places where animals are presumed to crowd together or were most likely to venture onto the road. For example, in Hawkes Bay, 81% of possum corpses were counted on or within 200 m of road bridges, and a disproportionate number of hedgehogs were also killed on bridges or approaches to bridges. At least in this area, human and animal traffic blackspots did not coincide. I suggest that this information could be useful to agencies controlling the spread of tubercular possums, and the technique of systematic counting of road‐kills could be extended to National Parks and other areas of natural interest.     

DETECTION OF SPECIES-SPECIFIC CALLS IN NOISE BY ZEBRA FINCHES POEPHILA GUTTATA AND BUDGERIGARS MELOPSITTACUS UNDULATUS: TIME OF FREQUENCY DOMAIN?

ABSTRACT

Two zebra finches and two budgerigars were trained, by operant conditioning, to detect autogenous (self-generated) distance calls in the presence of masking noise. For both species, there were no differences in detection thresholds for normal calls compared to time- reversed calls. Thresholds for autogenous calls were also compared with thresholds of the other species of birds listening to the same call. When detecting a zebra finch call, budgerigars had slightly lower thresholds than that of the zebra finch. On the other hand, when detecting a budgerigar call, zebra finches showed significantly higher thresholds than the budgerigar. From these results, and from what is known about basic hearing capabilities in these species, we conclude that these birds are not using a mechanism which utilizes “matched” or cross-correlational filtering. It is more likely that they are using “frequency-based” filtering in detecting calls in noise.     

The function of three main call types in common cuckoo

Acoustic signals play a key role in shaping the relationships in birds. Common cuckoos Cuculus canorus are known to produce various call types, but the function of these calls has only been studied recently. Here, we used a combination of field recordings (conducted in 2017) and playback experiments (conducted in 2018) to investigate the functional significance of common cuckoo calls. We found significant differences in the characteristics between male two‐element “cu‐coo” and three‐element “cu‐cu‐coo” calls, with these two call types being used in different contexts. The three‐element male “cu‐cu‐coo” calls were associated with females emitting their “bubbling” call. Playback experiments revealed that both males and females exhibit stronger responses to playing female “bubbling” calls than with the calls of the Eurasian sparrowhawk (Accipter nisus) serving as a control, suggesting a significant intraspecific communication function for this call type. However, we did not find any evidence to support mate attraction in male calls, as females were not stimulated by playback of male calls compared with sparrowhawk calls in the control group.     

ADAPTATIONS TO NESTING HABITAT IN THE REPRODUCTIVE BEHAVIOUR OF THE BLACK-BILLED GULL LARUS BULLERI

SUMMARY The nesting habitats adopted by most colonies of Black-billed Gulls Larus bulleri are river-beds that are subject to flooding. A number of respects in which the reproductive behaviour of Black-billed Gulls differs from that of at least most other gulls, such as Black-headed Gulls, can be viewed as adaptations, or byproducts of adaptations, to such nesting habitats:—

• (a) A different breeding site from the year before is often selected
• (b) The bulk of pair formation is accomplished before the gulls occupy their breeding sites; nesting territories are set up by mated pairs
• (c) In hostile encounters during the pair formation phase, site attachments are weak or transitory
• (d) In agonistic situations generally, attack thresholds appear to be relatively high, and fleeing thresholds relatively low
• (e) High intensity forms of“Choking” appear to be missing from the agonistic display repertoire
• (f) The growth of nest groups is rapid and orderly; nesting territories are small and the concentration of nests in the groups high
• (g) The time between occupation of the gullery site and the start of laying is short, and the synchrony of laying is high; this is probably related to the close proximity of the nests
• (h) The parents and young abandon the nest very soon after the egg hatch, and no “brood” nests are made
• (i) The young may develop locomotory powers more quickly than is the case in most other species; they can swim at an early age, and take to the water in tightly packed groups during alarms

The question of why these gulls should choose such vulnerable breeding sites is discussed.     

Visual processing of pictures

Word responses have been used to dedde whether pictures of expressive faces or postures portray truthful expressions. Previous investigators have assumed words are used only as symbols of “meaning”. They did not appreciate the use of words as symbols of “sorting”. If one viewer calls two photographs “angry” and another viewer calls the same two photographs “happy,” the viewers may disagree in their “meanings” but they agree in their ‘sortings” both agree each photograph portrays the same expression. Sorting groups reveal how the visual system processes photographic images.     

Decoding the ‘zeep’ complex: quantitative analysis of interspecific variation in the nocturnal flight calls of nine wood warbler species (Parulidae spp.)

ABSTRACT

The “zeep” complex consists of nine birds that produce nocturnal flight calls with similar acoustic features. Our inability to distinguish these calls inhibits the acoustic monitoring of these species. We test the hypothesis that flight calls of nine warblers in the “zeep” complex show sufficient acoustic differences to allow differentiation. We investigate divergence in these vocalizations by recording birds held for banding and collecting additional recordings from sound libraries. We used three approaches to compare calls between species: analysis of variance in acoustic properties, discriminant analysis of acoustic properties, and spectrographic cross-correlation. The first approach revealed five species that were different in one or more acoustic properties. The second approach revealed a level of assignment to the correct species (73%) that exceeded levels expected by chance (36%). The third approach revealed calls of seven species to be significantly more similar to conspecific calls than heterospecific calls. Our results suggest the calls of many members of the “zeep” complex exhibit species-specific differences in structure, which may allow differentiation of at least five “zeep” species based on call alone. We advocate for the combined use of these three approaches for the comparison of “zeep” calls in future flight call studies.     

基于线粒体ND2基因全序列探讨陕西红碱淖湿地繁殖鸥类的系统发育地位

本文对采自陕西红碱淖湿地繁殖的遗鸥(Larus relictus)、棕头鸥(L.brunnicephalus)、普通燕鸥(Sterna hirundo)和鸥嘴噪鸥(Gelochlidon nilotica)线粒体ND2基因全序列进行了测定和分析.联合已知该基因全序列的其他44种鸟类,重建了48种鸟类51个体之间的系统发育关系,并确定了4种鸥在系统发育中的地位.结果表明,4种鸥ND2基因全长均为1 041 bp;ML、MP和Bayes树拓扑结构大致相同,支持遗鸥划归为黑头鸥族(Black-headed species),棕头鸥划归为面具鸥族(Masked species),棕头鸥较为原始;普通燕鸥和鸥嘴噪鸥均隶属于黑帽族(Black cap species),鸥嘴噪鸥较为原始,处于分支底部,普通燕鸥与黑枕燕鸥(S.sumatrana)及与北极燕鸥(S.paradisaea)、南美燕鸥(S.hirundinacea)、南极燕鸥(S.vittata)聚类分支亲缘关系较近,但未能明确其具体分类地位;由于样品缺乏,鸥科(Laridae)、燕鸥科(Sternidae)和剪嘴鸥科(Rynchopidae)拓扑结构未能正确解析.     

Localization of Passerine Seeet and Mobbing Calls by Goshawks and Pygmy Owls

Goshawks and pygmy owls responded to recordings of passerine alarm calls by correctly orienting to their source. The seeet, or “aerial predator” alarm call which is generally assumed to be “non-localizable”, while it elicited fewer responses than did mobbing calls, was nevertheless accurately localized by all birds that did respond. The evolution of alarm calls is discussed in terms of efficient prey communication, following Darwin's “antithesis principle”, rather than predator selection for non-localizability.     

Ultrasonic Vocalizations of Six Taxa of Southern African Gerbils (Rodentia: Gerbillinae)

Ultrasonic calling during male-female encounters between individuals of the same species was investigated in six taxa of southern African gerbils, namely Tatera brantsii, Gerbillurus paeba paeba, G. p. cxilis, G. tytonis, G. setzeri, and G. vallinus. Vocalizations were detected by means of a bat detector utilizing a superheterodyne signal converter and a countdown circuit. Signals were recorded at audible frequencies and analysed with a sonograph. All taxa vocalized at ultrasonic frequencies by means of strongly modulated frequency “sweep” calls, which differed among taxa in duration, maximum and minimum frequency. “Clicks” were emitted by G. p. paeba and G. p. exilis, and G. tytonis emitted a “stutter” vocalization which consisted of a series of clicks. Long modulated “whistles” were identified from G. vallinus and T. brantsii at lower frequencies than “sweep” calls. Only one call type, a “sweep” call which differed in duration and frequency from all other taxa, was identified in G. setzeri. Cluster analysis was applied to the data using 7 acoustic characters. G. p. paeba and G. p. exilis displayed the highest similarity level between taxa and differed only in frequency of “sweep” vocalizations. G. paeba, G. tytonis and G. setzeri formed one cluster, while G. vallinus and T. brantsii formed a separate cluster. Numbers of calls in interspecific encounters were non-significantly less than in intraspecific encounters in all taxa except G. p. paeba, in which more vocalizations were recorded in inter- than intraspecific encounters. It is not clear whether species discrimination, measured by numbers of vocalizations in interspecific encounters, occurs.     

Birds and their food resources at Christchurch International Airport,New Zealand

The diversity and seasonal abundance of birds at Christchurch Airport, their food and feeding habits, and the phenology of the food resource were studied in 1968–69 as part of an investigation of the bird hazard to aircraft. The birds either fed and roosted on the airport or flew over or close to it. Seasonal trends in the diet of black‐backed gulls (Larus dominicanus), black‐billed gulls (L. bulleri), starlings (Sturnus vulgaris), and magpies (Gymnorhina tibicen hypoleuca) were determined by examining the gizzard contents of birds shot while they were feeding on the airfield. Marked food preferences were noticeably lacking, except that black‐backed gulls fed exclusively on earthworms. Black‐billed gulls, starlings, and magpies took a variety of insects, earthworms, arachnids, and, to a less extent, seeds. Species diversity, seasonal distribution, and abundance of invertebrates and seeds showed that the birds were opportunist feeders on a succession of temporarily abundant food, and their presence on the airfield was determined largely by the availability of invertebrates and seeds.     

Eavesdropping by Bats: The Influence of Echolocation Call Design and Foraging Strategy

We used playback presentations to free-flying bats of 3 species to assess the influence of echolocation call design and foraging strategy on the role of echolocation calls in communication. Near feeding sites over water, Myotis lucifugus and M. yumanensis responded positively only to echolocation calls of conspecifics. Near roosts, these bats did not respond before young of the year became volant, and after this responded to presentations of echolocation calls of similar and dissimilar design. At feeding sites Lasiurus borealis responded only to echolocation calls of conspecifics and particularly to “feeding buzzes”. While Myotis, particularly subadults, appear to use the echolocation calls of conspecifics to locate feeding sites, L. borealis appears to use the calls of a foraging neighbour attacking prey to identify opportunities for ‘stealing’ food.     

EQUIPMENT REVIEW

ABSTRACT

The Northern White Rhinoceros Ceratotherium simum cottoni is a subspecies of the White Rhino that is almost extinct in the wild. We studied the last reproducing herd kept in Zoo Dvur Kralove to describe its vocal repertoire. The calls produced by eight individuals were recorded and analysed as concerned both sound properties and behavioural contexts in which they were emitted. We distinguished 11 calls belonging to four categories: (1) tonal harmonic sounds, (2) puffing sounds, (3) growling sounds, and (4) repetitive sounds. We found an apparent similarity between acoustic parameters of homologous calls recorded in both white rhino subspecies. We further confirmed that the repertoire of white rhino calls is much larger than that reported in other rhino species. We tentatively interpret this finding as an adaptation to increased sociality. Four calls reach the infrasound range; nevertheless, they are probably not used for communication over distance. This is obvious in the case of the grouch call, which contains the highest infrasound component. There are, however, other candidates for such a communication function: the repetitive pant sound, which is not known in other rhino species. We hypothesise that the repetitions may enhance their audibility in the typical open habitats of white rhinos.     

7. THE ANGOLA KINGFISHER

Cantrell, M. A. &; Evans, S. M. 1981. Auditory communication in the blue waxbills Uraeginthus. Ostrich 52:104-107.

Field observations on the function of calls in the Redcheeked Cordon Bleu Uraeginthus bengalus, the Bluecapped Cordon Bleu U. cyanocephalus, and the Purple Grenadier U. (=Granatina) ianthinogaster were made in Kenya, East Africa. Individuals of all three species were usually seen in male-female pairs, and distinct calls were used to synchronize movement. Flight calls were made in rapid succession on take-off, but less frequently during flight. When birds on or near the ground became separated, repeated contact calls were used to locate and rejoin the partner. Alarm calls were rarely heard in the field, but usually originated from perched birds in relatively safe positions.

Laboratory experiments on the reactions of solitary caged birds to playback of calls were conducted using male U. bengalus. Separate playbacks of contact and flight calls both elicited a series of contact calls from the “lost” individual. In addition, a strong tendency to move towards contact calls was observed, the experiment confirming field observations that this call is used to locate and rejoin a partner after separation. Feeding birds usually flew up to perches in response to alarm calls and their own vocalizations were considerably reduced. The paper examines the function of these calls in pair synchronization and predator avoidance.     

Newly developed fungal diet for artificial rearing of the endangered long‐horned beetle Callipogon relictus (Coleoptera: Cerambycidae)

In this study, we attempted to develop an artificial diet to effectively rear the endangered long‐horned beetle Callipogon relictus Semenov to facilitate restoration efforts for this species. Fungal mycelia of the white‐rot fungus Pleurotus florida (Eager) were, for the first time, provided as an artificial diet for the larvae of C. relictus. The experiment started on August 11, 2015 with 53 larvae being provisioned with the fungal diet under laboratory conditions (25°C, 60 % RH, L:D 0:24) without diapause. During the first year, 11 adults (4 males and 7 females, 20.8 % of the 53 larvae) emerged between September 10 and October 1, 2016. The body length of the largest male was 106.8 mm, and three of the four males exceeded 100 mm in length. These results show that a fungal diet for rearing C. relictus is useful not only for reducing the larval period to approximately 1/6 of the normal larval period in nature, but also for producing large adults. These results support the notion that fungus may provide nutritional benefits during the larval development of C. relictus, and also indicate that this species is fungivorous.