1. Migration of Little Stint (Calidris minuta) at Eilat, Israel
Reuven Yosef
International Birding & Research Center in Eilat, P. O. Box 774, Eilat 88000, ISRAEL
Przemek Chylarecki
Gdansk Ornithol. Station, Nadwislanska 108, PL Gdansk 40, POLAND
Piotr Tryjanowski
Dept. of Avian Biol. & Ecology, A. Mickiewicz Univ., PL Poznan, POLAND

2. Migration similar to other Calidris species?
Migration & over-wintering
Sexual differences – Males migrate earlier?

3. Sex ratio of wintering birds
larger winter more northerly?
Males closer to breeding grounds?

4. Age, sex – adult M/F, juvenile M/F
Phenology in Julian dates

5. Bill length was calculated from total-head length as the two variables are highly correlated in Little Stints (r2 = 0.71) & enables a relatively accurate prediction using the formula: bill-length = 0.690*total-head – Underhill L.G., Tomkovich, P.S., Chylarecki P., Kania W., Hotker H., Hilden O., Summers R.W., Soloviev M.Y.& van Dijk K. (submitted Ardea) Breeding distribution and biometrics of Little Stints Calidris minuta.

6. Mass of stored fat estimated using equation developed for Little Stints wintering in NW Africa: fat mass = 0.596* body mass – 0.097*wing length ­– (r2 = 0.86; Piersma T. & Van Brederode N.E The estimation of fat reserves in coastal waders before their departure from northwest Africa in spring. Ardea 78: )

7. The annual cycle of Little Stints in Israel was divided into four periods: autumn migration wintering spring migration summer with cut-off points selected based on the numbers of birds caught at pentades 43/44 (summer/autumn), 70/71 (autumn/winter), 11/12 (winter/spring) and 30/31 (spring/summer).

8. Fig. 1. Numbers of Little Stint caught at Eilat by 5-day periods
Fig. 1. Numbers of Little Stint caught at Eilat by 5-day periods. Data for ; n=4849

9. Fig. 2. Age composition of Little Stints caught during autumn migration (pentades 44-70, n=3700) in 5-day periods.

10. Fig. 3. Variation in percentage of males among Little Stint caught during autumn migration (n=1670).

11. Fig. 4. Variation in percentage of males among adult Little Stints caught during summer and autumn migration (n= 950).

12. Table 1. Ancova on body mass with month, sex, age and structural size variables
Dependent Variable: MASS
_________________________________________________________________
Source Type III df Mean Square F Sig
Sum of Square
Corrected Model
Intercept
WING
HEAD
TARSUS+Toe
SEX
MONTH
SEX * MONTH
Error
Total
Corrected Total
R2 = .194 (Adjusted R2 = .185)

13. Fig. 5. Annual variation in average body mass of Little Stints by 10-d period. Sexes and ages combined.

14. Fig. 6. Variation in frequency of heavy Little Stints, i. e
Fig. 6. Variation in frequency of heavy Little Stints, i.e., those with estimated fat stores exceeding 5.5 g. Sexes & ages combined.

15. Fig. 7. Variation in frequency of very light birds - those with estimated fat stores less than 1.0 g. Sexes & ages combined.

16. CONCLUSIONS:
* Winter body mass in Israel similar to Little Stints wintering in sub-Saharan Africa in Mauritania (Piersma & Van Brederode 1990) and in Kenya (Pearson 1987).
* No increase in mid-winter body mass in birds wintering at Eilat. Similar to waders that winter in northern latitudes.Assumed that these stores act as a buffer against unpredictable weather. In Israel, no need to have such an 'insurance' against inclement weather.
*Autumn migration - 66% of birds at Eilat juveniles and is similar to 70% found by Gromadzka (1987) at Gdansk, Poland. On the other hand, on wintering grounds in Kenya, Pearson (1987) found that juveniles comprised 35-50% of the October-December samples.

17. CONCLUSIONS (continued):
* Greater body mass in autumn suggests a long non-stop flight.
* Negative fat stores obviously emaciated owing to catabolism of structural proteins.
*Biased sex ratio in favor of males suggests Little Stint females use other migration routes or wintering grounds than males of the same population.

19. * Possible that the discriminant function developed for Siberian Little Stints by Underhill et al. is not valid for the population migrating through Israel, and inflates the proportion of males in a sample.
*Pronounced seasonal variation in sex ratio among adult Little Stints on autumn migration: species' breeding system??

20. Fig. 4. Variation in percentage of males among adult Little Stints caught during summer and autumn migration (n= 950).

21. (From: Int. Wader studies 10. 1998.)
*Eilat