Sex-related differences in autumn migration timing of adult common sandpipersActitis hypoleucos(Linnaeus, 1758) (Charadriiformes: Scolopacidae)

Abstract

In the common sandpiper both sexes do not participate equally in brood rearing. The attendance of females progressively declines and by the third week after hatching, most of them leave their broods. To check if this unequal parental care results in different migration phenology of males and females, adult common sandpipers were caught at four ringing sites in Poland during their autumn migration and were sexed using a discriminant equation. The median date of female migration was 6 days earlier than that of males. In the first days of July, males comprised only 22% of common sandpipers caught, while later their percent share increased gradually and in August reached up to 80% of captured birds. However, birds of both sexes were present among migrants during the whole migration period and migration period of both sexes overlapped to a great extent. Most probably birds migrating through the study area came from a vast breeding area, where the period of egg laying differs between its northernmost and southernmost parts by at least 1 month.

Sexual size dimorphism and sex determination by external measurements in the Redshank Tringa totanus

“…If using these recommended border D values for the 962 adult Redshanks captured and measured in spring in southern Belarus and 78 birds caught in spring 2012 near Odessa, Black Sea coast (authors' unpublished data), respectively 55% and 54% of individuals would remain unsexed. Hence, a large sample of measured Redshanks is needed to find significant differences between sexes, as was shown for the Common Sandpiper (Meissner and Krupa, 2017). Furthermore, second-year Redshanks usually have heavily worn primaries in spring (Glutz von Blotzheim et al, 1977), which may lead to the underestimation of the wing length and a subsequent increase of incorrectly sexed birds.…”

“…The possibility of sex identification of birds has substantial importance for studies on different aspects of bird behavior (Mathot and Elner, 2004;Saino et al, 2010), migration phenology (Meissner and Krupa, 2017), and foraging strategies (Nebel, 2005). However, among waders, there are many species that exhibit very weak or even no plumage dimorphism between the sexes, but that differ in size, and this allows the efficient identification of sex by discriminant analysis (e.g., Meissner, 2005;Sikora and Dubiec, 2007;Hallgrimsson et al, 2008;Meissner and Pilacka, 2008).…”

Sexual size dimorphism and sex determination in Blacksmith LapwingVanellus armatus(Burchell, 1822) (Charadriiformes: Charadriidae)

“…The activities of male and female birds often differ, so sex identification becomes an important aspect of behavioural studies (Dit Durell et al 1993;Mathot & Elner 2004), migration phenology (Remisiewicz & Wennerberg 2006;Pinchuk et al 2016;Meissner & Krupa 2017) and foraging strategy (Nebel 2005;Castro et al 2009). Biological differences in the sexes are well described for species that show clear sexual dimorphism but are less known in species where the sexes do not differ noticeably in colour or size, which impedes studies of sex-specific patterns within a species (Newton 1998).…”

Sexing of common gull,Larus canus, using linear measurements

“…Hence, approaches based on discriminant functions using morphometric data from a sample of birds with known sex became a standard procedure in studies of monomorphic bird species from different families (Huynen et al 2003, Meissner 2005, Poisbleau et al 2010, Wojczulanis-Jakubas & Jakubas 2011. This procedure can also be useful for sexing individuals captured and measured a long time ago, which enables the reanalysis of existing data with new aims of testing sex dependent differences (Burger & Gochfeld 1981, Meissner 2015, Meissner & Krupa 2017. Discriminant functions are especially effective in the case of gulls (Laridae), allowing correct sexing from 90 to 100 % of individuals from different species (Mawhinney & Diamond 1999, Chochi et al 2002, Galarza et al 2008.…”