KOLONI BURUNG CANGAK ABU (Ardea cinerea LINNAEUS) DI AREA BANDAR UDARA INTERNASIONAL ADISUTJIPTO YOGYAKARTA (Grey Heron Colony (Ardea cinerea Linnaeus) in Yogyakarta Adisutjipto International Airport Area)

AbstrakBird strike merupakan peristiwa tabrakan antara burung baik secara berkelompok maupun tunggal dengan pesawat terbang pada proses penerbangan. Kejadian bird strike dapat menyebabkan kecelakaan ringan hingga serius yang sangat merugikan secara ekonomi Sekalipun telah dilakukan bird control secara maksimal berdasarkan panduan yang tersedia, namun bird strike juga terkadang masih terjadi di Bandar Udara Internasional Adisutjipto Yogyakarta (JOG) dengan tingkat kerusakan pesawat dari berat sampai ringan. Salah satu jenis burung penyebab kejadian bird strike di kawasan ini adalah cangak abu. Tujuan penelitian ini adalah mengetahui besaran dan prilaku koloni burung cangak abu (Ardea cinerea) pengunjung area. Pengambilan data besaran koloni burung pengunjung dilakukan dengan penghitungan langsung (sensus); perilaku selama di lokasi antara lain waktu dan arah datang dan pergi serta aktivitas yang dilakukan burung cangak abu selama di area bandara diamati dan dicatat secara langsung. Semua data yang diperoleh dianalisis secara deskriptif-kualitatif dan diperbandingkan burung lain dan hasil penelitian lain sehingga dapat diperoleh gambaran yang jelas tentang mengapa koloni cangak abu tersebut menjadi pengunjung area bandara. Hasil penelitian menunjukkan. Keberadaan burung cangak abu di Bandara Adisutjipto berpotensi relatif terbesar menimbulkan kejadian bird strike dibanding burung jenis lainnya karena jumlah individu harian yang datang terbanyak, frekuensi kedatangannya tertinggi kedua setelah burung wallet, ukuran tubuhnya yang relatif terbesar, terbang rendah, terbang pelan dan manuvernya juga lamban serta terbang menyilang landasan. Kondisi lingkungan area runway bandara yang luas, lapang terbuka, ditutupi hijauan rerumputan, berangin, aman dari predator, sepi jauh dari kegiatan manusia dan lokasinya yang strategis diantara zona roosting/nesting dan zona foraging/feeding menjadi lokasi yang ideal bagi koloni cangak abu untuk melakukan kegiatan harian loafing. Pengelola bandara JOG perlu meningkatkan kewaspadaan terhadap kemungkinan peningkatan kehadiran burung cangak abu, dan perlu memperluas jangkauan pengelolaan populasi cangak abu di luar wilayah bandara.AbstractBird strike is a bird collision event both in groups and singly with an aircraft in the flight process. Bird strike events can cause minor to serious accidents which are very detrimental to the economy. Although maximum bird control has been carried out based on the available guidelines, bird strikes also sometimes occur at Yogyakarta Adisutjipto International Airport (YAIA) with the level of aircraft damage from heavy to light. One type of bird that causes the bird strike incident at YAIA is grey heron. The purpose of this study was to determine the dayly individual number and behavior of the grey heron (Ardea cinerea), visitors to the YAIA area. Data collection on visitor bird colony size is carried out by direct count (census); behavior while in YAIA, including the time and direction of coming and going, and what the grey heron did during the airport area was observed and recorded directly. All data obtained were analyzed descriptively-qualitatively and compared to other birds and other research results so that a clear picture of why the colony of grey heron can be obtained as a visitor to the YAIA area. The results showed. the presence of grey heron (Ardea cinerea) at Adisutjipto Airport has the highest relative potential to cause bird strike events compared to other types of birds because the highest number of daily individuals, the second highest frequency of arrival after a glossy swiftlet, the largest relative body size, low flight, slow flight and maneuvers are also slow and fly across the runway. The YAIA runway area, which is wide, open and covered with grasses, windy, safe from predators, is quiet away from human activities and a strategic location between the roosting / nesting zone and the foraging / feeding zone makes it an ideal location for grey heron colonies to conduct colony of grey heron daily loafing activities. In conclusion, the manager of YAIA needs to increase awareness of the possibility of increasing the presence of grey herons, and it is necessary to broaden the scope of management of the grey heron population outside the YAIA region.

Separating noise and function in systems of animal communication: a comparative study of aggressive signaling in crayfish

ABSTRACTA primary issue in the study of dishonest signaling is the researcher’s ability to detect and describe a signal as being dishonest. However, by understanding the relative honesty of a signal as a statistical property of an individual or population, researchers have recently quantitively describe dishonest communication. Thus, dishonesty signals can be understood as when there is a breakdown in the correlation between a signal and its underlying meaning; creating variation within a signaling system. However, such variation in signaling systems may not be attributed to dishonesty, because of inherent noise within biological systems driven by evolutionary or physiological noise. Here, we try to separate out functional variation within honest or dishonesty signaling systems from inherent biological noise by leveraging homologous structures that have evolved for separate functions – the enlarged claws of freshwater crayfish. Because burrowing species of freshwater crayfish claws have not evolved as signals, the variability in the size and strength of their claws should be minimal when compared to claws of non-burrowing species that evolved as signals during aggression. We found that despite the claws of burrowing and nonburrowing crayfish claws having evolved to serve difference functions, the claws of all species in our study were inherently noisy. Furthermore, although claws that unreliably correlate to the strengthen the wielder may function as dishonest signals in other crustaceans, we did not find support for this hypothesis; because crayfish escalated aggression based on relative body size.

A test of male infanticide as a reproductive tactic in a cichlid fish

Infanticide and offspring cannibalism are taxonomically widespread phenomena. In some group-living species, a new dominant individual taking over a group can benefit from infanticide if doing so induces potential mates to become reproductively available sooner. Despite widespread observations of infanticide (i.e. egg cannibalism) among fishes, no study has investigated whether egg cannibalism occurs in fishes as a result of group takeovers, or how this type of cannibalism might be adaptive. Using the cooperatively breeding cichlid, Neolamprologus pulcher , we tested whether new unrelated males entering the dominant position in a social group were more likely to cannibalize eggs, and whether such cannibalism would shorten the interval until the female's next spawning. Females spawned again sooner if their broods were removed than if they were cared for. Egg cannibalism occurred frequently after a group takeover event, and was rarer if the original male remained with the group. While dominant breeder females were initially highly aggressive towards newcomer males that took over the group, the degree of resistance depended on relative body size differences between the new pair and, ultimately, female aggression did not prevent egg cannibalism. Egg cannibalism, however, did not shorten the duration until subsequent spawning, or increase fecundity during subsequent breeding in our laboratory setting. Our results show that infanticide as mediated through group takeovers is a taxonomically widespread behaviour.

Mammal faunal change in the zone of the Paleogene hyperthermals ETM2 and H2

"Hyperthermals" are past intervals of geologically rapid global warming that provide the opportunity to study the effects of climate change on existing faunas over thousands of years. A series of hyperthermals is known from the early Eocene (~ 56–54 million years ago), including the Paleocene–Eocene Thermal Maximum (PETM) and two subsequent hyperthermals (Eocene Thermal Maximum 2 – ETM2 – and H2). The later hyperthermals occurred during warming that resulted in the Early Eocene Climatic Optimum (EECO), the hottest sustained period of the Cenozoic. The PETM has been comprehensively studied in marine and terrestrial settings, but the terrestrial biotic effects of ETM2 and H2 are relatively unknown. Two carbon isotope excursions (CIEs) have been described in the northern part of the Bighorn Basin, WY, USA, and related to ETM2 and H2. An ~ 80 m thick zone of stratigraphic section in the extraordinarily dense, well-studied terrestrial mammal fossil record along the Fifteenmile Creek (FC) in the south–central part of the basin spans the levels at which the CIEs occur in the northern Bighorn Basin. High-resolution, multiparameter paleoecological analysis of this part of the FC section reveals two episodes of significant faunal change – faunal events B-1 and B-2 – characterized by significant peaks in species diversity and turnover and changes in abundance and relative body size. Faunal events B-1 and B-2 are hypothesized to be related to the CIEs in the northern part of the basin and hence to the climatic and environmental change of ETM2 and H2. In contrast with the PETM, change at faunal events B-1 and B-2 is less extreme, is not driven by immigration and involves a proliferation of body sizes, although abundance shifts tend to favor smaller congeners. The response at faunal events B-1 and B-2 is distinctive in its high proportion of species losses, potentially related to heightened species vulnerability in response to changes already underway in the lead-up to the EECO. Faunal response at faunal events B-1 and B-2 is also distinctive in that it shows high proportions of beta richness, suggestive of increased geographic dispersal related to transient increases in habitat (floral) complexity and/or precipitation or seasonality of precipitation.

Sexual dichromatism in a Mexican checkered beetle (Coleoptera: Cleridae: Neorthopleurinae)

This paper describes sexual dichromatism in the Mexican checkered beetle Nelsonoplium jeanae Barr, an unusual case for the Cleridae. Although sexual dimorphism is common in Cleridae, it is primarily expressed in morphological differences such as antennal composition, relative body size, shape of the hind legs, and the structure of the terminalia. Polychromatism is often encountered in clerids, with different color phena sometimes occurring within the same population. For example, Colyphus signaticollis Spinola presents in various concolorous, banded and striped elytral forms (Ekis 1977), and I have beaten several distinct morphs of this species (or near) from oak at the same location in Sonora, México. Solervicens (personal communication) has observed non sex–linked dichromatism among species of Eurymetopum Blanchard and within Pelonium Spinola. Much confusion has been attached historically to the identity of many species of the epiphloeine genus Ichnea Castelnau because earlier workers counted primarily on coloration to diagnose taxa. Recognizing the plasticity of elytral color pattern within the genus, and its unreliability for species determination, Opitz (2010) synonymized no fewer than 17 of the 31 previously described species. Solervicens’ (1986) study of Eurymetopum revealed that certain color morphs occur more frequently within one sex than the other, and he discusses a species within which the typical color pattern is expressed in males and some females while other females have their own distinct coloration, not found among males. Nevertheless, records of consistent sexual dichromatism in clerids are rare. Gerstmeier (2013) reports and illustrates a pair of an Indonesian Tenerus sp. where the male and female are so different in habitus and coloration from one another that they could easily have been mistaken for separate species had they not been collected in copula. As far as I am aware, the present note represents the first record of a North or Central American clerid exhibiting a similar dichromatism.