PACIENTES PORTADORES DE SONDA URINARIA.-

Three broad primary moult strategies were employed by first year Terek Sandpipers across the four populations studied: no replacement of juvenile primary feathers before starting the first adult moult aged c. 14 months; moulting a varying number of outer primaries (MOP) aged between four and seven months; and a complete, normal descendent moult starting aged about five months.

Kenya

382 birds were caught aged as first year of which 76 had moult scores that could be used to determine the moult strategy followed (Table 1, Fig. 1b). 306 (80%) were unmoulted birds caught between September and March for which it was impossible to tell what strategy they would follow and were thus omitted from analyses. No birds were found to undergo a complete moult of primaries. Most (78%) moulted 2–7 outer primaries (MOP2–MOP7). 22% did not moult at all (Fig. 1b). Those moulting some outer primaries were divided into MOP groups (Table 2). The majority (42%) moulted three primaries (MOP3). 75% moulted PP3-5 (MOP3–MOP5). The largest number of outer primaries moulted was seven (2%: MOP7) (Fig. 1b).

Moult was first observed during January; in this month, 18% of the sample of first-year birds were actively moulting outer primaries and 82% had not yet started moult, termed “unmoulted”, (n = 17) (Fig. 7a). In February this changes to 26% and 74% respectively (n = 34) and in March 72% of Kenyan immatures are moulting of which 22% have completed moult and 50% are in active moult, leaving 28% unmoulted (n = 32). The rate of birds starting moult slowed in April with 23% unmoulted (n = 26) and in May only three first year birds were caught of which none were unmoulted (Fig. 7a). Thus the period of primary moult for first year birds in Kenya covers January to May and probably into June, but lack of data from June do not allow confirmation of this.

North-western Australia

Moult scores were obtained from 931 first year Terek Sandpipers in north-western Australia for determining moult strategy. Three moult strategies were identified: 358 (38%) underwent a normal complete moult between November and March; 547 (59%) moulted varying numbers of outer primaries between October and May, and 26 (3%) did not moult any primaries (Fig. 1c). A further 84 (8% of total caught) first year birds were caught that were unmoulted and caught too early in the season to know which strategy they would follow. These were omitted from any analysis.

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For those that underwent a complete moult, the estimated average start date was 5 December, the average duration of moult was 109 days and thus the estimated end date was 25 March (Fig. 2c). Standard deviation in start date was 23 days on average thus giving an estimate of 95% of birds starting primary moult between 22 October and 21 January. Growth rate across the whole primary tract was 0.922%.

The estimated starting date for P1 when analysed alone was 4 December, similar to that for the whole primary tract together; the end of moult for P10 was 24 March (Fig. 3 and Table 3). A marked gap in the data during December and early January (Fig. 2) which is the early period of moult for first year birds, meant that the spread of data for the inner primaries was poor resulting in duration estimates for P1–P4 with large standard errors, and therefore not reliable (Table 3). No data of active moult for P5 was available and thus estimation of moult parameters was not possible (Fig. 3, Table 3). For the outer primaries, P8 to P10, duration of moult averaged c. 25 days and moult intervals were 5 to 13 days (Figs 4 and 5, Table 3). This meant a high level of overlap between these feathers during moult (Fig. 6). Due to sampling variability, growth rate seems to have been biased high for P4 and P6; P8–P10 had a relatively constant rate of growth of 0.6% PFMG per day (Fig. 6).

For the 931 birds that underwent a partial Moult of Outer Primaries (MOP), the first birds encountered moulting were in October (in this study, just one from six caught that month was in active moult: the outer two primaries on 24 October). In November 10% (n = 72) were actively moulting, the proportion increased in December to 31% (n = 16) and to 78% in January (n = 18). The first birds to complete the moult of the outer primaries were recorded in February (11%, n = 28) and in April 76% had completed (n = 97). By May the majority of them (97%, n = 90) had completed such that by June there were no actively moulting birds (Fig. 7b). Thus the period of moult was at least eight months (October, when aged about four months, to May, aged about 10 months) though duration for individual birds varied depending on whether only two or up to eight primaries are replaced.

The most commonly moulted number of primaries was five (MOP5: 28% of all MOP birds) with a further 44% moulting either four primaries (MOP4: 23%) or six (MOP6: 21%) (Table 2). Thus a total of 72% of birds moulted four, five or six outer primaries (Fig. 2c, Table 2). The same proportion of birds (11%) moulted the outer seven primaries (MOP7) as moulted only the outer three (MOP3). The maximum number moulted was eight (MOP8: 2%). No birds moulted nine outer primaries.

Birds moulting more outer primaries started moult earlier than those moulting less. Thus MOP7 was estimated on average to start moult on 3 December and have a duration of 122 days to end on 3 April (Fig. 8, Table 4). MOP5 was estimated to start 17 days later on 20 December and complete on 29 March (with a duration of 99 days). MOP4 was estimated to start three weeks later on 10 January

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and complete on 4 April. Results for MOP3 were illogical and unlikely to be correct given the low number of actively moulting birds in this group (Fig. 8, Table 4). Data for MOP1 and MOP2, MOP6 and MOP8 were insufficient to allow for an estimation of duration and start date. No birds showed MOP9. The estimated average end date for moult for MOP4, MOP5 and MOP7 all fell within a period of six days (Fig. 8, Table 4). There was a significant difference between the mean wing-length of birds that underwent a complete moult (mean = 131.8 mm, n = 358) and for those that underwent a ‘MOP’ moult (mean = 133.0 mm, n = 319; t = –3.29, df = 491.3, p < 0.05).

75 first year birds (8%) showed moult of both some inner and some outer primaries between January and June. The majority (67%) had moulted just one inner primary and more or less equal numbers had moulted between four and seven outer primaries (Table 5). Three had moulted eight outer feathers. 28% had moulted two inners and one bird in April had moulted three. Of 75 birds, 87% had suspended inner primary moult and the remaining 13% were in active moult.

South-eastern Australia

Eight birds caught in south-eastern Australia were aged as first years. A single bird was caught at the end of August and aged as a sub-adult having replaced all but the outer (very worn) primary and had suspended or arrested moult at that point. This moult would have taken place during its first year and is thus best considered as a first year moult (Table 1). One first year in July had all old,

unmoulted primaries, four, including the ‘sub-adult’ bird, had followed a normal descendent moult starting from the inner primaries. No birds exhibited moult of just some outer primaries (Fig. 1d).

The estimated start of moult was 26 January and the end as 13 May with a duration of 107 days. The average growth rate was thus 0.9337% of feather mass grown per day. With a standard deviation of 11 days, 95% of first year Terek Sandpipers in south-eastern Australia were expected to start moult between 4 January and 16 February (Fig. 2b).

India

Moult scores were recorded from 26 first year Terek Sandpipers. Only 12 could be used for analysis of which 50% moulted between one and three outer primaries, 42% did not moult during the non- breeding season and 8% underwent a complete moult (Fig. 1a). The remaining 14 birds were omitted from the analysis because they were caught early in the season, showing no moult (termed

“unmoulted”), so it was not possible to know which strategy they would follow.