Red-necked Phalaropes Phalaropus Lobatus Research Articles

Investigating the influence of the extreme Indian Ocean Dipole on the 2020 influx of Red-necked Phalaropes Phalaropus lobatus in Kenya

Ocean currents have wide-ranging impacts on seabird movement and survival. By extension, the extreme oscillations they are subject to, such as extreme Indian Ocean Dipole (IOD) events, can also be expected to dramatically influence seabird populations. This study links the extreme IOD event that occurred in 2019–2020 to the unusually high number of Red-necked Phalarope sightings observed in February 2020. We show that the extreme IOD event resulted in low net primary productivity (a measure of plankton growth) offshore from the Somalia-Kenyan coast, where Phalaropes have been tracked in previous winters. We suggest that Phalaropes were therefore forced to move closer to the coast to find food at river estuaries, thus explaining the influx in February 2020. This study calls for closer monitoring of seabird populations in East Africa, particularly during extreme IOD events, which are expected to become more common in the future.

Large-Scale Monitoring of Waders on Their Boreal and Arctic Breeding Grounds in Northern Europe

Large-scale and population-wide monitoring of waders on their boreal and arctic breeding grounds has hitherto been lacking, mainly because logistics are truly challenging in regions with few ornithologists, vast areas and few roads. In Norway, Sweden and Finland (here ‘Fennoscandia’) there are now national monitoring schemes in place, aimed at tracking all bird species, which allows trends to be estimated for northern wader populations. We present joint Fennoscandian population trends for 24 wader species, covering the period 2002–2013 (in some cases somewhat shorter time periods). The data stem from 1263 routes in Norway, Finland, and the northern two thirds of Sweden, all situated north of 58°N. This area of one million km2 largely coincides with the boreal and arctic parts of Fennoscandia. The trends found are rather evenly distributed between strong increases and strong declines. Trends do not differ between short- and long-distance migrants, nor do they vary in relation to breeding latitude. Ringed Plover Charadrius hiaticula, Wood Sandpiper Tringa glareola, Green Sandpiper T. ochropus and Common Redshank T. totanus had significant positive trends, whereas Common Snipe Gallinago gallinago, Ruff Philomachus pugnax and Spotted Redshank Tringa erythropus were declining significantly in numbers. Trends could be calculated even for relatively uncommon breeding birds such as Temminck's Stint Calidris temminckii, Eurasian Dotterel Charadrius morinellus, Broad-billed Sandpiper Limicola falcinellus, Jack Snipe Lymnocryptes minimus and Red-necked Phalarope Phalaropus lobatus, although these trends build on few routes and individuals, and thus have low precision. The monitoring schemes in Norway and Finland are expected to increase in coverage in the coming years, with up to a total of 1555 northern routes being tracked when the schemes are fully developed. This should enable still more robust trend estimates for northern waders on their Fennoscandian breeding grounds to be calculated in the future.

Fine-scale biophysical interactions drive prey availability at a migratory stopover site for Phalaropus spp. in the Bay of Fundy, Canada

We examined the role of biophysical interactions in structuring the foraging habitat of phalaropes Phalaropus spp. at an important migratory stopover site in the Bay of Fundy. We sampled both biological and physical aspects of the environment and integrated these observa- tions into generalized additive models (GAMs). Strong tidal currents interact with steep bathy- metric gradients at the Brier Island ledges to enhance vertical mixing, creating dense surface aggregations of Calanus finmarchicus copepods at fine temporal and spatial scales. The resulting spatial variation in copepod density in near-surface waters creates a highly heterogeneous foraging environment for phalaropes, which are obligate surface feeders. Models of phalarope abundance over the ledges suggested that phalaropes forage on upwelled zooplankton aggrega- tions as they drifted downstream. Our results highlight the importance of considering underlying physical processes when assessing hotspots of prey aggregations for marine species, particularly within highly dynamic systems such as the Bay of Fundy. This is particularly relevant to consider- ations of the conservation status of red-necked phalaropes Phalaropus lobatus, which have aban- doned a long-time migratory stopover area previously used by more than one million birds during the mid-1980s.

Wader, gull and tern population estimates for a key breeding and stopover site in Central Kazakhstan

SummaryPopulation size estimates of waders, gulls and terns passing through or breeding in Central Asia are very scarce, although highly important for global flyway population estimates as well as for targeting local conservation efforts. The Tengiz-Korgalzhyn region is one of the largest wetland complexes in Central Asia. We conducted surveys in this region between 1999 and 2008 and present estimates of population size as well as information on phenology and age structure for 50 species of Charadriiformes. The Tengiz-Korgalzhyn wetlands are especially important for Red-necked Phalaropes Phalaropus lobatus and Ruffs Philomachus pugnax with, respectively, 41% and 13% of their flyway populations using the area during spring migration. The region is also an important post-breeding moulting site for Pied Avocets Recurvirostra avosetta and Black-tailed Godwits Limosa limosa used by, respectively, 5% and 4% of their flyway populations. Besides its key importance as a migratory stopover site, the study area is a key breeding site for the Critically Endangered Sociable Lapwing Vanellus gregarius, the Near Threatened Black-winged Pratincole Glareola nordmanni and for Pallas’s Gull Larus ichthyaetus with 16%, 6% and 5% of their world populations, respectively. We identified 29 individual sites that held more than 1% of the relevant flyway populations of at least one species of Charadriiformes. Including data on other species of waterbirds (mainly waterfowl), there were 93 sites that qualify for Important Bird Areas (IBA). About half of them are protected in a state nature reserve, while an additional 20% are recognised as IBAs. Nevertheless, 28 important sites are currently not recognised as IBAs nor are they protected by other conservation means. These sites require conservation attention.

Fugler i Norge i 2005 - Rapport fra Norsk faunakomité for fugl (NFKF)

THE NORWEGIAN BIRD REPORT 2005 - a report on locally uncommon and scarce birds in Norway in 2005, by the Norwegian Birds Records Committee (NFKF) The basis of this report is the annual reports produced by the county rarities committees. For 2005 all the counties on the mainland contributed to the report, although Finnmark, Troms, Sogn & Fjordane, Rogaland and Vest-Agder counties did not publish own county reports. Svalbard archipelago and Jan Mayen did not contribute to this report. We believe this report reflects fairly well observations from Norway in 2005. Readers should take care to note the geographical or time delimitation of the records stated for the different species, as stated in codes immediately after the scientific name of the species. The Norwegian Birds Records Committee (NFKF) has been publishing annual reports since 1991. The occurrence of Bewick’s Swan Cygnus columbianus was the poorest in NFKFs history, and the occurence of Lesser White-fronted Geese Anser erythropus at the traditional feeding and roosting site at Valdakmyra, Porsanger (FI) continued to be very low. White-fronted Geese Anser albifrons were seen in poor numbers, while Bar-headed Geese Anser indicus were seen in record high numbers. Mandarin Ducks Aix galericulata occurred in high numbers. Gadwalls Anas strepera have occurred in steadily increasing numbers in Norway in recent years, and 2005 was the best year to date for this species. Garganeys Anas qurquedula had a poor year. Quail Coturnix coturnix occurred in good numbers for the fourth year in succession. Yellow-billed Divers Gavia adamsii experienced the second best year since 1991. Due to favourable weather conditions in late August both Sooty Shearwaters Puffinus griseus and Manx Shearwaters Puffinus puffinus occurred in record high numbers. Many Rough-legged Buzzards Buteo lagopus were seen during the winter months. The Eurasian Hobby Falco subbuteo is a raptor that has occurred in high numbers in recent years, and 2005 was the third best year ever. The occurrence of Avocets Recurvirostra avosetta was very poor. Several shorebirds, such as Ringed Plover Charadrius hiaticula, Northern Lapwings Vanellus vanellus, Sanderlings Calidris alba and Bar-tailed Godwits Limosa lapponica were reported in high numbers from mid-January following the winter storm «Inga». The number of migrating Broad-billed Sandpipers Limicola falcinellus, Black-tailed Godwits Limosa limosa and Red-necked Phalaropes Phalaropus lobatus were the second best in NFKFs history. Migrating Pomarine Skuas Stercorarius pomarinus was seen in good numbers. Iceland Gulls Larus glaucoides occurred in record high numbers while the occurrence of Little Gulls Larus minutus and Glaucous Gulls Larus hyperboreus was the third best in NFKFs history. The occurrence of Black Terns Chlidonias niger was very poor. Wood Larks Lullula arborea occurred in record high numbers. The negative trend related to migrating Horned Larks Eremophila alpestris continued in 2005 and the last six years represent the six poorest years for this species. Red-throated Pipits Anthus cervinus had another poor year, while Richard’s Pipits Anthus richardi occured in record high numbers. The occurrence of Yellow Wagtails Motacilla flava flavissima was the poorest in NFKF’s history. Stonechats Saxicola torquata occurred in record high numbers and seventeen confirmed breeding pairs were recorded from coastal areas. The Mistle Thrush Turdus viscivorus is probably expanding significantly in the north of its distribution range. The number of singing Common Grasshopper Warblers Locustella naevia and the occurrence of Yellow-browed Warblers Phylloscopus inornatus was the best ever recorded. The number of Barred Warblers Sylvia nisoria was the second best in NFKF’s history. The number of Great Grey Shrikes Lanius excubitor was the highest ever recorded. Two-barred Crossbills Loxia leucoptera and Pine Grosbeaks Pinicola enucleator occurred in poor numbers. The Ortolan Bunting Emberiza hortulana still has a negative trend and is disappearing from former breeding areas. The Rustic Bunting Emberiza rustica experienced the poorest year in NFKFs history, while the occurrence of Little Buntings Emberiza pusilla was the best ever recorded.

Mate guarding, copulation strategies and paternity in the sex-role reversed, socially polyandrous red-necked phalarope Phalaropus lobatus

In a recent review, Westneat and Stewart (2003) compiled evidence that extra-pair paternity results from a three-player interaction in which sexual conflict is a potent force. Sequentially polyandrous species of birds appear to fit this idea well. Earlier breeding males may attempt to use sperm storage by females to obtain paternity in their mate’s subsequent clutches. Later-breeding males may consequently attempt to avoid sperm competition by preferring to pair with previously unmated females. Females may bias events one way or the other. We examined the applicability of these hypotheses by studying mating behavior and paternity in red-necked phalaropes (Phalaropus lobatus), a sex-role reversed, socially polyandrous shorebird. Male red-necked phalaropes guarded mates more strongly than other shorebirds. Males increased within-pair copulation attempts during their mate’s fertile period, and maintained or further increased attempts towards the end of laying, suggesting an attempt to fertilize the female’s next clutch; these attempts were usually thwarted by the female. Paired males sought extra-pair copulations with females about to re-enter the breeding pool. Multilocus DNA fingerprinting showed that 6% of clutches (4/63) each contained one chick sired by a male other than the incubator, producing a population rate of these events of 1.7% (n=226 chicks). Male mates had full paternity in all first clutches (n=25) and 15 of 16 monogamous replacement clutches. In contrast, 3 of 6 clutches of second males contained extra-pair young likely fathered by the female’s previous mate. Previously mated female phalaropes may employ counter-strategies that prevent later mating males from discriminating against them. The stability of this polyandrous system, in which males provide all parental care, ultimately may depend on females providing males with eggs containing primarily genes of the incubating male, and not a previous mate.

Prey switching in red-necked phalaropes Phalaropus lobatus: Feeding limitations, the functional response and water management at Mono Lake, California, USA

The ability of red-necked phalaropes Phalaropus lobatus to switch prey under conditions of changing prey abundance at Mono Lake, California, was tested in order to predict the potential effects of continued water diversions there on migratory waterbird populations. Red-necked phaloropes cannot switch prey because they are incapable of surviving on a diet of just the hardier of two invertebrates threatened by salinity increases at Mono Lake. Individuals experimentally limited to brine shrimp Artemia monica as a primary prey source lost mass rapidly until death ensued, or until they were offered other prey. These data show that a marked preference for one prey may indicate important physiological limitations in a predator. Such limitations may partly explain Murdoch's empirically supported prediction ( Ecol. Mongr. (196), 39, 335-54) that prey switching will not occur where strong prey preferences exist. These results also indicate that strong prey preferences of migratory birds can, and probably should, help determine water management policy at wetlands of importance to shorebirds, especially in cases where initial prey diversity is low.

Male choice and sperm competition as constraints on polyandry in the red-necked phalarope Phalaropus lobatus

The mating system of the red-necked phalarope Phalaropus lobatus is usually classed as polyandrous, but studies show that the majority of females are monogamous. Polyandry appears to be constrained because later arriving males do not usually nest with females that have already laid a clutch that season (C1-females), despite the sexual receptiveness of these females. Rather they nest with females that have not previously laid a clutch that season (C0-females). Five potential explanations of this constraint on polyandry were tested. Two hypotheses, invoking female-female competition, were not supported as female agonistic success appeared to be unrelated to priority of access to males, and there was no apparent difference between C0- and C1-females in their ability to find unpaired males. Two hypotheses suggest that C0-females are preferred by males either because they can initiate a clutch more rapidly or because they lay larger eggs. Neither hypothesis was supported by the available data. The data upheld a third male choice hypothesis that C1-females are discriminated against because they have copulated previously with another male and this may compromise paternity. Secondary males copulated and attempted to copulate more often when paired with C1-females, suggesting that sperm competition was greater and confidence of paternity was lower. Corroborative evidence of active male choice showed that males were more aggressive towards associating C1-females than towards C0-females, although how males discriminated between the two classes of females was not determined.

On a Red-necked Phalarope encountered a typhoon during migration

The migration of red-necked phalarope Phalaropus lobatus, is normally wholly pelagic but coastal stragglers may occasionally appear. When especially a strong low pressure area in spring is travelling north-east along the coast, small number of migrants may occasionally move inshore to avoid the spring storm. Red-necked phalaropes are too light (See Table 1.) to remain water-borne in strong gales, and tend to be driven to leeward.Like a temperate low pressure, typhoon can be disastrous. On Aug. 30 in 1970, seven phalaropes were found dead inland after the typhoon No. 12 as shown in Fig. 2, had passed. They probably, encountered the typhoon during flight at night were whipped off its gales and driven inland. Striking against a structure seemed to be the cause of their death.