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During studies on the etiology of puffinosis, a disease of the Manx shearwater, 1 to 4% of full-grown birds were found to have dry, non-pigmented lesions on the webs of the feet. Poxvirus infection was detected in six of seven full-grown birds with such lesions. The lesions contained large encapsulated inclusions which were packed with mature and immature poxvirus particles. Poxvirus infection was not apparent in shearwater fledglings during puffinosis epizootics, and its spatial distribution was not related to that of puffinosis. The results indicate that poxvirus infection produces a mild, self-limiting disease in shearwaters and is not the cause of puffinosis.

OBSERVATIONS OF A MIXED-SPECIES FLOCK OF BIRDS FORAGING ON EUPHAUSIIDS NEAR ST. MATTHEW ISLAND, BERING SEA GEORGE L. HUNT ]R.,1 NANCY M. HARRISON, 1 WILLIAM M. HAMNER,2 AND BRYAN 5. 0BST 2 'Department of Ecology and Evolutionary Biology, University of California, Irvine, California 92717 USA, and 'Department of Biology, University of California, Los Angeles, California 90024 USA ABSTRACT.-We observed mixed-species flocks of birds foraging for euphausiids near Cape Upright, St. Matthew Island. Murres (Uria spp.) predominated, and the number present was equivalent to 79% of the murres breeding at Cape Upright, or 11% of the total St. Matthew population. All bird species actively feeding were catching the euphausiid Thysanoessa raschii. SCUBA divers determined that murres were diving deeper than 30 m; schools of euphausiids were not observed above that depth. Injured and disoriented euphausiids were present near the surface where surface-feeding Black-legged Kittiwakes (Rissa tridactyla) captured them. Received 20 April 1987, accepted 16 January 1988. LARGE mixed-species seabird flocks feed in the vicinity of the Pribilof Islands (Hunt et al. 1978, Hunt unpubl. data) and at St. Matthew Island. The flocks are com posed typically of large numbers of diving species, the majority murres (mostly Thick-billed Murres, U. lomvia, with some Common Murres, U. aalge), with smaller numbers of Crested Auklets (Aethia cristatella), Least Auklets (A. pusilla), Parakeet Auklets (Cy- clorrhynchus psittacula), and Horned Puffins (Fra- tercula corniculata). In addition to these diving species, several surface-foraging species are regularly in attendance. These include North- ern Fulmars (Fulmarus glacialis), red Phalaropes (Pha/aropus fulicaria), and Black-legged Kitti- wakes (Rissa tridactyla). For these mixed-species flocks, when prey identity was known, eu- phausiids were the primary food item in the guts of all species. Euphausiids occur in the diets of most species of seabirds in the Bering Sea (Sanger and Baird 1977, Hunt et al. 198la). These crustaceans are particularly important for migratory Short-tailed Shearwaters (Puffinus tenuirostris) and for several species of breeding alcids (Bedard 1969, Hunt et al. 198l a, Schneider et al. 1986). During the day euphausiids usually migrate away from the surface, and in the shallow (30-60 m) shelf re- gions of the Bering Sea probably aggregate close to the bottom (S. Smith pers. comm.), where they are relatively inactive and densely packed (Mauchline and Fisher 1969). The diurnal cap- ture of euphasuiids by birds able to dive to depths where euphausiids concentrate is not surprising. However, the regular occurrence of euphausiids in the gut contents of diurnal, sur- face-foraging Black-legged Kittiwakes raises the question of how they obtain this prey. On 21, 27, and 28 June 1984 we encountered large mixed-species flocks near St. Matthew Is- land over water approximately 62-64 m deep (Fig. 1). We investigated one segment of the flock on 27 June. We mapped the distribution of foraging birds, collected biirds for stomach- content analysis, and put SCUBA divers in the water to observe underwater prey distribution and bird foraging. METHODS We counted birds along a series of transects east of Cape Upright (Fig. 1). Continuous counts were made of all birds within a 90 arc from the bow to the beam and extending to 300 m from the ship on the side with the best visibility. The sea was calm, and visi- bility was excellent for counting birds. Birds on the water were tallied separately from flying birds, and only birds on the water were used to determine for- aging distributions. Data were entered directly into a microcomputer custom programmed with data-en- try software (l:Jpdegraff and Hunt 1985) that permit- ted continuous records of bird numbers. From approximately 1500 to 1900 local time, we collected actively foraging seabirds. Diving species observed returning to the surface were selected, as were surface-foraging species seen dipping or peck- ing at the surface. We removed stomachs from birds within 1 h of collection and preserved the crops, stomachs, and their contents in 80% ethyl alcohol. We obtained information on the near-surface and The Auk 105: 345-349. April 1988

lhe Manx Shearwater Puffinus puffinus is the commonest shearwater in the western ralearctic, with two sub-species being found in the Mediterranean. 1he Puffinus p. mauretanicus of the Balearics, and the Puffinus Ps yelkouan of the eastern Mediterranean, including the Maltese Islands, 1he Manx Shearwater is a common br&8ding visitor to the Maltese Islands., N/A

The distribution patterns of aerial seabirds are analysed from counts made in the Prydz Bay region, Antarctica, during the African legs of SIBEX I and II in late summer (end of February to April), and compared with those made farther west at the same time of year during FIBEX. Species composition and abundances were similar in all three surveys, with sooty shearwaters Puffinus griseus contributing approximately half of the total aerial bird energy demand. Differences between surveys are explained in terms of longitudinal or seasonal differences in sampling areas and periods. Correlations between bird distribution patterns and environmental parameters are used to infer the scale-dependent factors affecting bird dispersion at sea. Two macro-scale bird assemblages, identified by physical parameters, were separated along latitudinal gradients (temperature and salinity) associated with the Antarctic Divergence. These assemblages are consistent with the Intermediate and Southern High Latitude Groups identified during FIBEX. At smaller spatial scales, almost all species were correlated with the abundance of Antarctic krill Euphausia superba, both across the entire SIBEX I grid, and within the areas north and south of the Antarctic Divergence. Similarly, during SIBEX II, seabird densities were six times greater when krill was abundant than when krill was scarce. Sooty shearwaters, which appeared to be moving through the area, were the only abundant bird species not correlated with krill abundance. Possible reasons why previous studies have not detected correlations between seabird and krill abundances are discussed.

The presence of the Storm petrel Hydrobates pelagicus on islands close by the large Mediterranean port of Marseille is surprising to say the least, and yet the Storm petrel was known as a breeding species on the “Archipel de Riou” during the mid-nineteenth century (Jaubert & Barthelemy-Lapommeraye, 1859). In 1915 a few pairs were reported breeding on the island of Riou (L’Hermitte 1915–16), and by 1918 large breeding colonies were found on “Ile Plane” and the two rocky islets: the “Grand and Petit Congloues” (Lavauden & Mourgue, 1918). In the spring of 1923 Heim de Balsac (1923) visited Riou, but gave no indication that the Storm petrel bred there. However, he did visit Ile Plane and found many petrels “apparently sleeping in recesses in the rocks”. In early April 1924 he visited the “Grand Congloue” and found Cory’s shearwater Calonectris diomedea and the Levantine race of the Manx shearwater Puffinus p. yelkouan occupying nest sites, but the Storm petrel was absent. Heim de Balsac & Mayaud (1932) again visited Ile Plane on 9 May 1931 and counted 40 petrels. The two fresh eggs found indicated that the breeding season had only just begun. Fifteen years later Storm petrels were still breeding on Ile Plane, some even nesting under dense low bushes (A. Rivoire pers. com.).

Organochlorine residues were sought in 26 specimens of Greater Shearwater (Puffinus gravis) and Sooty Shearwater (P. griseus) collected in August, 1974 from the southeastern approaches to the Bay of Fundy. Residue levels of DDTs, PCBs, dieldrin, oxychlorodane, mirex and HCB in depot fat, liver, and muscle are reported. HCB was present at the same order of magnitude in both species; all other contaminants were significantly higher inP. gravis than inP. griseus. Levels of all compounds except mirex and HCB were higher in the depot fat of femaleP. gravis than in males.

Balearic Shearwaters P. puffinus mauretanicus (= Puffinus yelkouan mauretanicus, a better name according to Bourne 1982 and unpublished report) have long been known to be regularly present along the French Atlantic coast during the summer months (Mayaud 19 32). A preliminary estimate of their numbers was recently obtained by studying the density of birds at sea (“Programme C.R.B.P.O.-M.E.R.”: Hemery et al. 1986): 10,000 to 15,000 individuals are thought to be simultaneously present in mid-summer from southern Biscay to southern Brittany (Yesou 1985). Their distribution is far from homogeneous, and a major concentration occurs in the area we studied near Les Sables d’Olonne (46°30 N, 1°50 W: fig. 1). Les Sables d’Olonne is the fifth most important fishing port in France according to total tonnage discharged, the first for inshore fishery. The latter activity attracts foraging shearwaters, and could explain their important numbers here.

An analysis has been made of the fungi recorded on feathers removed from living birds and incubated in moist chambers. Penicillium spp. and Oidiodendron spp. were the most widespread and the most frequently observed fungi, while Chrysosporium spp. and Arthroderma curreyi, although frequently recorded, were not as widespread. In general there were some differences between the fungi present on birds with different feeding habits, while there was a marked association between A. curreyi and Turdus spp., and between Chrysosporium spp. and Procellaria puffinus.

as Schweinfurth (1961) has demonstrated very well in this journal. Perhaps the geographical facet of the natural history of these birds which has most signi ficance is that of their migrations (fig. 1). This is best documented in the case of the Bass Strait muttonbird or Short-tailed Shearwater, Puffinus tenuirostris (Ser venty, 1953 & 1956; Marshall & Serventy, 1956). Preceded by their parents, the fledglings in their hunger leave their rookeries in late April and early May. Shortly afterwards casualties are picked up along New Zealand beaches. By May the birds are found in numbers in Japanese seas; in July-Septem ber, they are over Bering Straits, Alaskan coastal waters and even reach into the Arctic Ocean. The

Mushin, Rose (University of Melbourne, Victoria, Australia) and Frances M. Ashburner . Gastrointestinal microflora of mutton birds ( Puffinus tenuirostris ) in relation to “limy” disease. J. Bacteriol. 83: 1260–1267. 1962.—The aerobic bacterial intestinal flora of mutton birds, healthy and affected with “limy” disease, was investigated, mainly in birds from Great Dog Island, Bass Strait, Australia. A total of 1,274 specimens from gut on post-mortem and from cloacal swabs was examined. No indication was obtained of a pathogenic bacterial species concerned in “limy” disease. A study was made of the types of organisms and their distribution in the gut of mutton birds. The sparsity, or occasional absence, of aerobic bacterial flora in some birds, especially adults, was noticed. The “limy” birds, by comparison with normal chicks, had a richer flora more evenly distributed through the alimentary canal. A higher ratio of gram-negative to gram-positive bacterial types was recorded in chicks; adult birds had a lower or an even numerical ratio. The comparatively frequent occurrence of Proteus species, except P. mirabilis , and of irregular and intermediate coliform types was evident. Escherichia coli type I was not a constant inhabitant of the gut. The gram-positive flora consisted mostly of Staphylococcus saprophyticus, S. lactis , and Enterococcus. The possibility that “limy” disease may be caused by physiological factors is discussed.

This paper reports the first comprehensive surveys of Fea's Petrel (Pterodromafeae), Bulwer's Petrel (Bulweria bulwerii), Manx Shearwater (Puffinus puffinus), Little Shearwater (Puffinus assimilis baroli) and two temporally-segregated forms of Band-rumped Storm-petrel (Oceanodroma castro) in the whole Azores archipelago, conducted from 1996 to 1998. Listening to nocturnal vocalizations was the main survey method. Breeding of Fea's Petrel was not confirmed and new sites of Bulwer's Petrel were not found (previous status: one site, 50 pairs), but previously undocumented colonies were identified for the remaining species. Manx Shearwater occurred in four colonies with 115-235 pairs (previous status: probable breeder), Little Shearwater occurred in 28 colonies with 840-1,530 pairs (previously: four locations, >150 pairs), hot-season Band-rumped Storm-petrels occurred in 5 colonies with 250-300 pairs (previously: two locations, 200 pairs) and cool-season Band-rumped Storm-petrels were found in eight locations with 665-740 pairs (previously: three locations, 600 pairs). Most colonies were confined to precipitous cliffs and islets, which may be a result of predation threats by introduced mammals. Although these surveys provided a valuable revision of the status and distribution for these species of conservation concern, further survey work is warranted and target areas are indicated. We discuss the potential and limitations of listening for nocturnal vocalizations as a method to survey and monitor shearwater and petrel populations in inaccessible habitats. Received 24 May 1999, accepted 8 July 1999.

During a three month research cruise near the island of South Georgia, sea surface temperature (SST) increased from c. 2°C to over 4°C. Satellite derived SST show that this corresponded to a rapid southward and eastward shift of isotherms in the northern Scotia Sea, which could have resulted from changes in the wind field. At the same time, observation from the ship of seabirds close to the island indicated changes in the abundance of some non-resident species, whereas resident breeders from South Georgia, such as black-browed albatrosses (Diomedea melanophris) and prions (Pachyptila spp.) which were foraging locally, were present at consistent density in both halves of the survey. Blue petrels (Halobaena caerulea) left the area after breeding, so were associated only with the low water temperatures during the first part of the cruise. In contrast, great shearwaters (Puffinus gravis) and soft-plumaged petrels (Pterodroma mollis) migrated into the area later in the survey. These birds were almost certainly non-breeders which were feeding in the warmer water which had moved towards the island.

Audubon’s Shearwater Pufhnus lherminieri is a little known species of petrel. The recent descriptions of a possibly new species (P. atrodorsalis) and a new subspecies (l? 1. colstoni) have suggested that the population breeding on Reunion Island, I! 1. bailloni, may represent a key taxon for understanding the phylogeography of this group in the Indian Ocean. We provide the first detailed information on distribution, abundance, habitat characteristics and breeding biology of the species on Reunion, and assess relationships between the Indian Ocean taxa based on biometrics, coloration characters and patterns of breeding phenology. We also studied the behaviour of the birds on Reunion, paying particular attention to vocalizations. Analysing the parameters that affect calling rate, such as moonlight, season and time, we show that calling activity can be used to estimate colony size. Using this method, we sampled more than half of Reunion Island habitats suitable for Audubon’s Shearwater, and estimate that the breeding population there is between 3000 and 5000 pairs in at least 235 colonies. Compared to other Indian Ocean populations (n = 136 specimens), the analysis of biometrics and coloration characters suggests that three main populations exist (Comoro, Reunion and Seychelles), with birds of Maldives and Amirantes being biometrically inseparable from those of Seychelles, and birds from Aldabra being intermediate between Seychelles and Reunion. The proposed new species, atrodorsalis, also falls in the overlap between Seychelles and Reunion birds, which argues against a full species taxonomic status.

Long-lived migratory animals must balance the cost of current reproduction with their own condition ahead of a challenging migration and future reproduction. In these species, carry-over effects, which occur when events in one season affect the outcome of the subsequent season, may be particularly exacerbated. However, how carry-over effects influence future breeding outcomes and whether (and how) they also affect behaviour during migration and wintering is unclear. Here we investigate carry-over effects induced by a controlled, bidirectional manipulation of the duration of reproductive effort on the migratory, wintering and subsequent breeding behaviour of a long-lived migratory seabird, the Manx shearwater Puffinus puffinus. By cross-fostering chicks of different age between nests, we successfully prolonged or shortened by ∼25% the chick-rearing period of 42 breeding pairs. We tracked the adults with geolocators over the subsequent year and combined migration route data with at-sea activity budgets obtained from high-resolution saltwater-immersion data. Migratory behaviour was also recorded during non-experimental years (the year before and/or two years after manipulation) for a subset of birds, allowing comparison between experimental and non-experimental years within treatment groups. All birds cared for chicks until normal fledging age, resulting in birds with a longer breeding period delaying their departure on migration; however, birds that finished breeding earlier did not start migrating earlier. Increased reproductive effort resulted in less time spent at the wintering grounds, a reduction in time spent resting daily and a delayed start of breeding with lighter eggs and chicks and lower breeding success the following breeding season. Conversely, reduced reproductive effort resulted in more time resting and less time foraging during the winter, but a similar breeding phenology and success compared with control birds the following year, suggesting that 'positive' carry-over effects may also occur but perhaps have a less long-lasting impact than those incurred from increased reproductive effort. Our results shed light on how carry-over effects can develop and modify an adult animal's behaviour year-round and reveal how a complex interaction between current and future reproductive fitness, individual condition and external constraints can influence life-history decisions.

Correct species identification is a crucial issue in systematics with key implications for prioritising conservation effort. However, it can be particularly challenging in recently diverged species due to their strong similarity and relatedness. In such cases, species identification requires multiple and integrative approaches. In this study we used multiple criteria, namely plumage colouration, biometric measurements, geometric morphometrics, stable isotopes analysis (SIA) and genetics (mtDNA), to identify the species of 107 bycatch birds from two closely related seabird species, the Balearic (Puffinus mauretanicus) and Yelkouan (P. yelkouan) shearwaters. Biometric measurements, stable isotopes and genetic data produced two stable clusters of bycatch birds matching the two study species, as indicated by reference birds of known origin. Geometric morphometrics was excluded as a species identification criterion since the two clusters were not stable. The combination of plumage colouration, linear biometrics, stable isotope and genetic criteria was crucial to infer the species of 103 of the bycatch specimens. In the present study, particularly SIA emerged as a powerful criterion for species identification, but temporal stability of the isotopic values is critical for this purpose. Indeed, we found some variability in stable isotope values over the years within each species, but species differences explained most of the variance in the isotopic data. Yet this result pinpoints the importance of examining sources of variability in the isotopic data in a case-by-case basis prior to the cross-application of the SIA approach to other species. Our findings illustrate how the integration of several methodological approaches can help to correctly identify individuals from recently diverged species, as each criterion measures different biological phenomena and species divergence is not expressed simultaneously in all biological traits.

Inter-seasonal events are believed to connect and affect reproductive performance (RP) in animals. However, much remains unknown about such carry-over effects (COEs), in particular how behaviour patterns during highly mobile life-history stages, such as migration, affect RP. To address this question, we measured at-sea behaviour in a long-lived migratory seabird, the Manx shearwater ( Puffinus puffinus ) and obtained data for individual migration cycles over 5 years, by tracking with geolocator/immersion loggers, along with 6 years of RP data. We found that individual breeding and non-breeding phenology correlated with subsequent RP, with birds hyperactive during winter more likely to fail to reproduce. Furthermore, parental investment during one year influenced breeding success during the next, a COE reflecting the trade-off between current and future RP. Our results suggest that different life-history stages interact to influence RP in the next breeding season, so that behaviour patterns during winter may be important determinants of variation in subsequent fitness among individuals.

Background Establishing patterns of movements of free-ranging animals in marine ecosystems is crucial for a better understanding of their feeding ecology, life history traits and conservation. As central place foragers, the habitat use of nesting seabirds is heavily influenced by the resources available within their foraging range. We tested the prediction that during years with lower resource availability, short-tailed shearwaters (Puffinus tenuirostris) provisioning chicks should increase their foraging effort, by extending their foraging range and/or duration, both when foraging in neritic (short trips) and distant oceanic waters (long trips). Using both GPS and geolocation data-loggers, at-sea movements and habitat use were investigated over three breeding seasons (2012–14) at two colonies in southeastern Australia. Results Most individuals performed daily short foraging trips over the study period and inter-annual variations observed in foraging parameters where mainly due to few individuals from Griffith Island, performing 2-day trips in 2014. When performing long foraging trips, this study showed that individuals from both colonies exploited similar zones in the Southern Ocean. The results of this study suggest that individuals could increase their foraging range while exploiting distant feeding zones, which could indicate that short-tailed shearwaters forage in Antarctic waters not only to maintain their body condition but may also do so to buffer against local environmental stochasticity. Lower breeding performances were associated with longer foraging trips to distant oceanic waters in 2013 and 2014 indicating they could mediate reductions in food availability around the breeding colonies by extending their foraging range in the Southern Ocean. Conclusions This study highlights the importance of foraging flexibility as a fundamental aspect of life history in coastal/pelagic marine central place foragers living in highly variable environments and how these foraging strategies are use to buffer this variability.

We studied short-tailed shearwaters Puffinus tenuirostris foraging near the Pribilof Islands, Alaska, USA, during the summers of 1987, 1988, and 1989. Their foods were almost exclusively the euphausiid Thysanoessa raschii, which they obtained both from near-surface swarms and from epibenthic layers. Near-surface mating swarms of euphausiids occurred in areas of elevated phytoplankton standing stocks near inshore tidal fronts. Many of these euphausiids had attached spermatophores. Shearwaters also obtained euphausiids over shallow reefs and inshore of the fronts where euphausiids were trapped in water shallower than 40 m by irregularities in bottom topography ('bathymetric traps'). We hypothesize that the largely inshore distribution of shearwaters in the southeastern Bering Sea described by previous workers is the result of attraction of shearwaters to frontal areas where euphausiids may forage on phytoplankton stocks throughout the summer. These areas, when shallower than 40 m, would also permit shearwaters to access epibenthic aggregations of euphausiids during daylight, when euphausiids not engaged in mating swarms usually migrate to depth.

Multivariate analyses were used to assess the independent determinants of four organochlorines (OCs) in the fat and eggs of breeding female Great Shearwaters Puffinus gravis. The amounts of polychlorinated biphenyls (PCBs), DDE, DDT, and dieldrin, in both adult fat tissue and in eggs were positively correlated. However, there was no correlation between the amounts of OCs in adults and their eggs. Positive correlations between the amounts of different OCs in adults and in eggs suggest that individual differences in non-breeding range, diet and age are determinants of pollutant levels within a species. The mass of ingested plastic was positively correlated only with PCBs, a group of chemicals commonly found in plastics. It is probable that seabirds assimilate PCBs and other toxic chemicals partly from ingested plastic particles.

The role that population-level competition plays in regulating foraging distributions of colonial breeders has remained elusive because many studies of animal movements in the nat- ural environment focus on relatively small datasets from a single population of animals. Here, we present a large (528 foraging trips, 169 individuals), multi-year, multi-colony GPS tracking dataset mostly collected simultaneously at 4 breeding colonies across the core breeding range of a colo- nially breeding pelagic seabird, the Manx shearwater Puffinus puffinus. Foraging areas were identified by filtering GPS locations (using speed, time of day, and turning angle), validated on a subset of 25 birds carrying co-deployed depth loggers to maximise inclusion of foraging and feed- ing behaviour. Foraging areas showed high annual variation, but consistent patterns emerged. Birds from each colony consistently foraged locally, showing little overlap between colonies, but birds from all 4 colonies sometimes travelled large distances to forage within a single relatively restricted area. This combined pattern may be driven by density-dependent competition relatively locally, with high overlap and resource sharing at a distance, facilitated by a dual foraging strat- egy of mixing short and long trips. The key shared area was located near to a tidal front system, the Irish Sea Front, and the stratified waters of the Western Irish Sea to its north and west, which are characterised by high productivity. Visits to this area declined with increasing colony distance, suggesting that foraging advantages are balanced by the energetic costs of travel. Nevertheless, this area is probably of key importance to birds breeding at colonies across the species' core breeding range, highlighting the potential connectedness, and therefore vulnerability, of a pelagic species via a single foraging location, despite apparent segregation more locally around the breeding colonies.

We compared seasonal composition, abundance, and biomass of seabirds between the Northeast (ICES region) and Northwest (NAFO region) Atlantic fisheries regions to identify differences in community assemblage and prey consumption. Seabirds were more abundant in the Northwest Atlantic, but biomass was greater in the Northeast. This disparity resulted from enormous numbers of little auks Alle alle breeding in West Greenland and of Leach's storm-petrels Oceanodroma leucorhoa breeding in Newfoundland, plus large numbers of non-breeding shearwaters Puffinus spp. entering southern NAFO areas in summer. The Northeast Atlantic communities were dominated numerically by northern fulmars Fulmarus glacialis, large auks Uria spp., and the Atlantic puffin Fratercula arctica. Seabirds occupying the North Atlantic consume approximately 11 × 106 t of food annually. Overall consumption rates peak during summer as a result of increased breeding activity and seasonal movements of birds into the North Atlantic. Because of the greater biomass of birds in the northeast, consumption (mainly by piscivores) in ICES areas was approximately 20% higher than that in NAFO areas, where planktivores dominate. NAFO areas had, however, a much greater consumption rate per unit area than ICES areas. Comparative studies such as these could prove informative in assessing large predator responses to the influence of fishing and ocean-scale climate change.

(1982). Feeding Methods of the Short-Tailed Shearwater Puffinus Tenuirostris. Emu - Austral Ornithology: Vol. 82, No. 4, pp. 226-227.

At times two species of euphausiids (Nictyphanes australis and N. capensis) and three species of hyperiid amphipods (Hyperia luzoni, Parathemisto gandichaudii, and P. gracilipes) occur in swarms close to the shores of the Snares Islands. Four species of birds (Daption capense, Diomedea bulled, Lams novaehollandiae, and Puffinus griseus) and six species of fish, including four reef fish (Latris lineata, Mendosoma lineatum, Notothenia angustata, N. microlepidota, Pseudolabrus cinctus and P. fucicola), were observed feeding on these Crustacea. These swarms seem to be important to the Snares Islands ecosystem as food for the large populations of petrels breeding there.

Experimental Demonstration of an Internal Rhythm of Reproduction in a Trans-Equatorial Migrant (The Short-Tailed Shearwater Puffinus Tenuirostris)

Marshall and Serventy1 have recently directed attention to moult adaptation in the short-tailed petrel, Puffinus tenuirostris, of Tasmanian waters. In this species post-nuptial head and body moult takes place in the breeding quarters while moult of tail- and wing-feathers is postponed until the bird has arrived at its northern non-breeding quarters. From this the authors decide that “from the … data there emerges clear evidence of the evolution of a moult adaptation related to the migratory requirements of species that undergo a long post-nuptial migratory movement”. That moult adaptation in relation to long-distance migration need not be a general phenomenon, and probably has only taken place in certain families of birds, is indicated by the following observations on two species of long distance passerine migrants. In April 1953 a large number of swallows, chiefly consisting of the European swallow, Hirundo rustica, and the European house martin, Delichon urbica, perished in the neighbourhood of Cape Town, due to a short spell of adverse weather conditions. Of the thirty-five H. rustica examined, 99.1 per cent showed moulting flight-feathers, 65.7 per cent had moulting tail-feathers and 8.6 per cent had moulting body- and head-feathers. Of fifty-two D. urbica, 40.4 per cent had moulting wing-feathers, 75 per cent moulting tail-feathers and 94.2 per cent moulting body- and head-feathers2.

Several instances of natural infection with agents of the psittacosis-lymphogranuloma venereum group (PL) have been reported in sea birds (Meyer, Amer. J. Opthalmol. 63: 1225/199-1246/220, 1967), but only one of a PL isolate from ectoparasites of these birds. This was an isolate from chiggers (Trombiculidae) on a shearwater ( Puffinus baroli ) in the USSR (Terskikh, Cheltsov-Bebutov, Kuborina & Keleinikov, Vopr. Virus. 6: 131–35, 1961). A recent review of PL isolates from ectoparasites is given by Eddie, Radovsky, Stiller & Kumada (Amer. J. Epidemiol. 90: 449–60, 1969).

IN the years 1946 and 1947, epizootics have been observed among the manx shearwaters on the island of Skomer off the Pembrokeshire coast1. The birds affected have been juveniles nearly ready to leave the island. The disease is characterized by the occurrence of large blisters on the web, either plantar or dorsal surfaces. In 1946 severe conjunctivitis was also a notable feature, but was rare in 1947. Some birds show spasm of the legs shortly before death. It is estimated that at least 90 per cent of the birds with clinical signs die of the disease.

A male specimen was captured off the coast of Iwate Prefecture and the testis was fixed with Hermann's solution.The spermatogonial complex was found to contain 84 chromosomes. The macro-chromosome group comprises six pairs, being 12 in number. They are represented by the formula aV+bV+cR+dr+ev+fr. The micro-chromosomes are 72 in number, showing a variation in shape ranging from small rods to spherules.Based on the observations of the primary spermatocyte the haploid number of chromosomes was found to be 42. This result serves to confirm the diploid number observed in the which contains spermatogonial metaphase.According to Oguma (1937), the chromosomes of the Leach's fork-tailed petrel (Oceanodromal. leucorrhoa Vieillot) belonging to the related family, Procellariidae, the chromosome formula is given as 6R's+68r's. Thus, the Leach's fork-tailed petrel is remarkable in having the complex no V's and J's.In comparison with the chromosomes of Puffinus leucomelas here concerned there is no similarity between the two species, so far as the chromosome morphology is concerned.

Along a 12 km. section of beach near Miyazaki, Kyushu, an estimated total of 2, 520 dead Slender-billed Shearwaters Puffinus tenuirostris (6-15 per 100 m.) was counted on May 22 and June 5, 1964 by Mr. Y. Nakajima, Miyazaki University. Similar mass mortality has been reported during the same period along Shikoku to Suruga Bay washed by Kuroshio Current (cf. Reports by Ozawa and Kawaguchi et al., 1964, Misc. Rep. Yamash. Inst. no. 22).The oceanographical condition in these waters had been very unusual during spring to summer in this year possibly with the change of plankton distribution (details not yet published) and occasional strong south winds were frequent. The shearwaters devor plankton on arrival to these Japanese waters from the southern hemisphere probably in rather exhausted condition and, although most flock should have made northward safely even though the usual food in these southern Japanese waters were scarce, some flocks would have encountered stormy weather to be weakened to death.Inspite of the similar migration, the Sooty Shearwater P. griseus was not found among them, as far as samples collected are concerned. It might be considered that the Slender-billed be weaker physiologically and is more liable to death when encountered stormy weather in exhausted condition (as also reported in Australian waters (Gibson & Sefton, 1955: Emu 55)). If so, this occasional high mortality might counter-balance the increase of its especially abundant population.

Ixodes philipi n. sp. is described from 2 females associated with Puffinus leucomelas or Oceanodroma castro , Sanganjima Island, Iwate Prefecture, Japan. The male, nymph and larva are unknown.

(1) A small population of short-tailed shearwaters has been monitored each year since 1947. Survival rates have been calculated from the disappearance of marked individuals and related to breeding experience. (2) Shearwaters breeding for the first time had a relatively high rate of mortality. This rate then decreased considerably and remained low for about ten years before increasing substantially in older birds. (3) The sex of a shearwater, the period when it was active in the colony and whether or not it had been born in the colony had no major impact on the length of its breeding lifetime. (4) Increasing offspring production was associated with a decreasing mortality rate early in a shearwater's breeding career but not in mid-life. Later in its career, higher offspring production was associated with an increasing rate of mortality. (5) The log proportional hazard regression model and GLIM algorithm used attempted to avoid some of the problems inherent in analysing age-dependent survival in long-lived species.

burrow nesters, thereby possibly serving as a defense mechanism for the former. Because the oil floats on top of the stomach contents it is ejected most frequently but solid and partly-digested food may follow it. Early analyses of stomach oil from Sooty Shearwaters (Puffinus griseus; Smith 1911, Carter 1921, Carter and Malcolm 1927) and from a Fulmar (Fulmarus glacialis; Rosenheim and Webster 1927) revealed high concentrations of wax esters. In these lipids the fatty acids are esterified with long-chain alcohols, whereas in typical fats (triglycerides) they are esterified with glycerol. Because wax esters were then virtually unknown in marine animals, though known to occur in large quantities in Sperm Whales (Physeter macrocephalus; Smith 1911, Carter 1921), hypotheses were put forward to explain their origin. Carter and Malcolm (1927) considered that they might be indigestible residues from food but failed to find them in an analysis of fish and shell-fish fats (littoral and epipelagic species). They and Rosenheim and Webster (1927) independently made similar hypotheses, based on similar reasoning: the stomach oils might be secretions of the birds themselves, similar to preen gland wax but possibly originating near the nasal cavity (Rosenheim and Webster 1927), or actual preen gland wax accidentally ingested (Carter and Malcolm 1927). Matthews (1949) found evidence suggesting that the proventriculus could be the site of secretion but he emphasized that proof of a secretory origin was still required. No such proof appears to have been published but, until very recently, some ornithologists have given unwarranted credence to this hypothesis (see Ashmole 1971). A number of biochemical studies (table 1) have now revealed that petrel stomach oils are not uniform: wax esters, triglycerides and glyceryl ethers have variously been found to be the predominant lipids, and proportions have varied widely even among samples taken from the same species at the same time. It was mainly this variability that cast doubt on the secretion hypothesis (Lewis 1969), for it seemed unlikely that a secretory mechanism would vary its product so much. The hypothesis, first advanced by Hagerup (1926), of a dietary origin for the oils seemed more likely. Kritzler's (1948) experiment with a captive fulmar, which regurgitated oil resembling pork fat after being fed fatty pork (but no biochemical tests were made) tended to support this hypothesis. On the basis of their studies of petrel stomach oils, Lewis (1969) and Cheah and Hansen (1970 a,b) independently concluded that the oils were not secretions but derivatives of the diet.