KONING FJ (1982) On phenology and biometry of Rock and Water Pipit Anthus spinoletta. LIMOSA 55 (4): 115-120.

Water Pipit Anthus spinoletta Rock Pipit Anthus petrosus = Anthus spinoletta littoralis Occurrence and biometry of Rock Pipits Anthus spinoletta littoralis and Water Pipits A. s. spinoletta were studied in an area near Zandvoort (Noord-Holland). Identification of both subspecies has been summarized in tab. 1. In most years Rock Pipits arrived earlier in autumn than Water Pipits (fig. 1). The first Rock Pipit was recorded one month earlier on the average than the first Water Pipit. Passage of Rock Pipits peaked in the first decade of October (fig. 2). Water Pipits wintered in the area in small numbers. Data on wing length, tarsus length and weight are given in tab. 2. From the distribution of wing lengths (fig. 3) it is concluded that the sex ratio of Rock Pipits was equal in contrast with Water Pipits in which males appeared to dominate. In The Camargue sex ratio of Water Pipits was equal. More information on sex ratio of Water Pipits is needed to clarify the phenomenon. First of all more data on sex ratio in NW-Europe are necessary

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