INFECCIONES URINARIAS EN PACIENTE SONDADO.- SONDADO.-

and Australia

Introduction

Moult is one of three key activities in the annual life cycle of any migratory bird together with breeding and migration (Ginn and Melville 1983, Zenatello et al. 2002, Newton 2009). However, for a number of species which do not breed aged one year, breeding is not something that an immature bird needs to fit into the first one-and-a-half annual cycles. In long-distance migrant waders, the immatures of many species remain on or near their non-breeding grounds instead of migrating to the breeding grounds with the adults (Pearson 1974, Elliott et al. 1976, Prater et al. 1977,

Remisiewicz 2011). First year birds and those entering their second year in these species are therefore not limited by the time constraints faced by adults which have to complete moult in time to fatten up and migrate back to the breeding grounds. Furthermore, while the structure and condition of juvenile plumage (grown before fledging) are weaker and of lower quality than the plumage of an adult (Dwight 1900, Prater et al. 1977, Ginn and Melville 1983), it has only had to transport the bird on one migration, from breeding to non-breeding grounds. Adult primaries, on the other hand, by the time the bird returns to its non-breeding grounds, have been used to make the migration in both directions. Therefore, adults urgently need to replace their feathers upon arrival at the non-breeding grounds, attested by the often heavily worn primaries of adults in

August/September); in contrast juveniles arrive at the non-breeding grounds with relatively unworn feathers which can last many more months of wear before needing replacement (Pearson 1974, Tree 1974, Prater et al. 1977).

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The moult strategies of immature birds differ from those of adults (Elliott et al. 1976, Prater et al. 1977, Prater 1981, Svensson 1992, Remisiewicz et al. 2010a) with a wide variety of strategies employed. Of those that do migrate to the breeding grounds at the end of their first year, some do not moult at all, such as for the majority of first year Marsh Sandpipers Tringa stagnatilis in East Africa, and thus migrate north on the same juvenile primaries they travelled south with (Pearson 1974, Prater et al. 1977). Others moult all of their primaries prior to return migration e.g. Little Stint Calidris minuta and Ringed Plover Charadrius hiaticula in East Africa (Stresemann and Stresemann 1966, Dean 1977, Pearson 1984). Others undergo only a partial moult involving some of the outer primaries as in Wood Sandpiper Tringa glareola and Ruff Philomachus pugnax (Schmitt and Whitehouse 1976, Pearson 1981, Remisiewicz et al. 2010b) prior to returning north. For those that do not migrate, a common strategy e.g. in Curlew Sandpiper Calidris ferruginea et and Grey Plover Pluvialis squatarola (Elliott et al. 1976, Paton and Wykes 1982, Serra et al. 1999) is to replace varying numbers of outer primaries and then to undergo a complete normal moult from May or June as ‘second year’ or ‘sub-adults’ to complete in advance of returned adults (Serra et al. 1999). There are species which, within the same non-breeding population, exhibit more than one of these strategies to a greater or lesser degree e.g. Semi-palmated Sandpiper Calidris pusilla and Ruff (Prater et al. 1977, Pearson 1981).

The Terek Sandpiper Xenus cinereus is a long-distance migrant wader which breeds across the Western Palearctic between c. 70°N and 50°N and from Finland in the west to Kamchatka in the east (Cramp and Simmons 1983, Van Gils et al. 2016). The entire population migrates south to spend the boreal winter near or south of the equator, along coastlines of East Africa, the Middle East, central and eastern Asia south to south-eastern Australia (del Hoyo et al. 1996, Delany et al. 2009). Adults return to breed the following boreal spring but most first year birds remain on or near the non- breeding grounds for another year and only return to breed at two years of age (Waltner and Sinclair 1981, Cramp and Simmons 1983, Hayman et al. 1986). Little has been published on the moult

strategies of Terek Sandpipers and in particular on that of immatures. Furthermore, only a small number of regional comparisons of moult strategies of immature long-distance migrants have been undertaken (Remisiewicz et al. 2010b, Summers et al. 2010). In this chapter, the moult strategies of immature Terek Sandpipers (birds aged up to 20–22 months old) are described for three widely separated localities and compared between four non-breeding localities spread between 9°N and 38°S. Distinct patterns are noted and possible reasons for these suggested.

Methods

Terek Sandpipers were caught, ringed and primary moult scores obtained in Kenya, India and Australia. In Kenya birds were ringed during regular wader-ringing sessions at Mida Creek (3°19′S

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39°57′E) between 1978 and 2014. In India, data were collected during wader ringing carried out at Mandapam (9°17′N, 79°8′E) and at the Great Vedaranyam Swamp (10°18′N, 79°51′E) in south- eastern India between 1985 and 2014. In Australia, data were collected during wader ringing activities between 1982 and 2012 by the Australian Wader Study Group in north-western Australia (19°15′S 120°20′E) and south-eastern Australia (38°22′S 145°32′E). First year (0–12 months), sub- adult (those finishing their first year of life and entering the second year) and adult birds were distinguished as far as possible using Prater et al. (1977) and previous experience. Further details on location and methodology were described in Chapter 1.

First year birds were assessed according to the extent of moult undertaken: no moult, partial Moult of Outer Primaries (MOP), and complete moult. Birds following the MOP strategy were further divided into groups according to the number of primaries moulted. Thus a bird that moulted one outermost primary was placed in group MOP1, birds moulting two outer primaries, in MOP2 etc.

Birds found in moult had moult scores recorded following the standard method devised by Ashmole (1962) and Ginn and Melville (1983) where an old, unmoulted feather is scored '0', a new fully- grown feather is scored '5' and the stages in between are scored 1 – 4. Feathers are numbered descendently, so that the inner primary, usually first to moult, is P1 and the outer primary, P10 (Ginn and Melville 1983).

Sub-adult birds frequently showed two cycles of moult: the first year moult that was either complete or nearing completion, and freshly-moulting inner primaries as part of the sub-adult or first adult moult cycle. For these birds, where the moult pattern allowed clear distinguishing (typically first year moult being several months earlier than sub-adult or adult moult), the first year moult was used in the first year moult analysis and the fresh, moult score in the sub-adult moult analysis. Where it was not clear, the moult score was discarded on the assumption that such a moult strategy could be equally undertaken by any bird. It is impossible to test for this with the given dataset, but in reality there might be a bias here in that a certain ‘quality’ of bird could moult sooner and thus show a clear strategy, and thus be the subset sampled, while others of perhaps a ‘poorer quality’ would not and thus be omitted.

Moult scores were converted to proportion of feather mass grown (PFMG) as described in Chapter 1. For calculating PFMG in Terek Sandpiper moult, relative primary masses were obtained from Terek Sandpipers in Australia (C. D. T. Minton unpubl. data) following the methodology laid out by Summers et al. (1983) and Underhill and Joubert (1995).

Estimates of start date and duration of moult were calculated using the Underhill-Zucchini moult model using Type 2 data (Underhill and Zucchini 1988) where data were sufficient to run the model. The analysis was performed using the R moult package (Erni et al. 2013). For first year results, the

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analysis for Type 2 data was used and for sub-adults in north-western Australia the analysis for Type 4 data. For sub-adults in Kenya, since birds which had completed moult were not distinguished from adults, the data best fit Type 5 for analysis.

Results