What difference in migratory patterns has been tracked between birds banded at the Crozet Islands versus the Kerguelen Islands?
Their precise foraging grounds and the extent of their oceanic wanderings appear distinct.
Tracking data reveals that even closely situated populations within the Southern Indian Ocean exhibit behavioral separations that contribute to speciation. For instance, populations originating from the Crozet Islands display migratory patterns that markedly differ from those originating at the Kerguelen Islands. While both groups inhabit the broader Southern Ocean, the data suggests their precise foraging grounds and the average extent of their oceanic movements are not identical. The Kerguelen birds might remain more consistently within the Indian Ocean basin, or they may display different average route preferences compared to the Crozet birds, which could favor certain sectors of the Atlantic or Pacific, thereby creating reproductive barriers through differential resource exposure.
