The Kentish plover Charadrius alexandrinus is a small ground-nesting shorebird which breeds in temperate and subtropical environments including the Arabian Peninsula. At the Arabian Peninsula ground temperature frequently exceeds the tolerable maxima for eggs and parents, reaching 60°C at midday in summer. Breeding ecology, parental behaviour, distribution and population trends of Kentish plovers in Saudi Arabia are poorly known, and therefore, the first objective of my PhD is to investigate how the extreme hot environment influences their parental care and mating systems. To address this objective, I used video surveillance and transponder systems to record the incubation routines of male and female plovers at their nests over 24 h, and used mixedeffect models to test parental cooperation. I show that ambient temperature has a significant influence on incubation behaviour of both sexes: biparental care – a proxy variable of cooperation between parents – was particularly strong at midday with incubation shared approximately equally between the male and the female (Chapter 2). I suggest parental cooperation is essential to protect the eggs from excessive heat. I experimentally tested this proposition in Chapter 3. Some Kentish plovers nest under bushes and they and their eggs are thus shaded, whereas others nest in the open and are fully exposed to sun. As I expected, the parents coordinate incubation behaviour at exposed nests more precisely than those at covered nests (Chapter 3). In Chapter 4 I investigated the potential impact of the extreme environment on breeding ecology, and show high rates of both mate fidelity and nest-site fidelity, whereas brood desertion was rare - unlike in most other populations that have been studied (Chapter 4). My second objective is to use the Kentish plover as a model species to map spatial distribution in order to identify potential sites that require high conservation priority. To model spatial distribution of plovers I used Generalised Linear Models (GLMs) with four habitat variables derived from remotely-sensed data. I show that Kentish plovers prefer coastal habitats at low elevations, far from settlements, with high soil moisture and low vegetation cover. Based on this model I recommend locations for potential protected areas to be established on the Red Sea coast of Saudi Arabia. I argue that the Kentish plover could be used as a flagship species for designation of new protected areas and thus conservation of Kentish plover habitat will not only protect this species, but will benefit other shorebird species particularly those with similar habitat requirements.
|Date of Award||1 May 2010|
|Supervisor||Tamas Szekely (Supervisor)|
- hot environment
- parental cooperation
- remote sensing