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11 th International Symposium for GIS and Computer Cartography for Coastal Zones Managementmother-calf groups inside Jervis Bay (Figure 1a). Results of the Moran’s I statistic allowed for rejection of the nullhypothesis, that sightings of both mother-calf and non-calf groups were randomly distributed within the study area.There was a clear geographic variability between the distribution of mother-calf humpback whale pairs and noncalfgroups. A greater proportion of mother-calf pairs were distributed within Jervis Bay with 89% within the MarinePark boundary. A significant cluster of high mother-calf group sightings (‘hotspots’) occurred within JervisBay, extending 1.5 km from the entrance on the seaward side and across most of the Bay in waters greater than 12 min depth. There were clusters of low mother-calf group sightings (‘cold spots’) north and south of Green Point and inthe deeper ocean waters outside the Bay. A significant cluster of high non-calf group sightings (‘hotspots’) occurrednear the Bay entrance and extended north and south along the coast adjacent to the entrance. Clusters of low noncalfgroup sighting frequencies occur within the Bay. The proportion of non-calf whale group sightings within theJervis Bay Marine Park was 49%.A. B.C.Days Sighted (%)100%80%60%40%20%0%MayJuneJulyAugustSeptemberOctoberNovemberMother-calfGeographic variability was observed between mother-calf humpback whale groups and non-calf groups duringthe southern migration period with mother-calf groups indicating higher usage of the coastal embayment of JervisBay, on the south eastern Australian coast. Several studies undertaken in humpback whale breeding grounds haveconcluded that mother-calf pairs show a significant preference for warm, shallow water, relative to other group types(eg. Smultea, 1994; Ersts and Rosenbaum, 2003). The current study demonstrated similar findings, with mother-calfpairs displaying a significant preference for the protected shallow waters inside Jervis Bay during the southern mi-Mother-calfescortAdultAdult-juvenileFigure 1. Spatial clusters of high and low humpback whale sightings between 2007 and 2010 and proportion of different groupcompositions across the survey months. High Getis-Ord Gi * z-scores depict more intense clustering of high whale sighting frequencies(‘hotspots’), shown in red, and low z-scores depict more intense clustering of low whale sightings, shown in blue (‘coldspots’). A) High and low areas of mother-calf group sighting frequencies; B) High and low areas of non-calf group sightingfrequencies; and C) Proportion of days in which each whale group composition was sighted per across the study period.Discussion and conclusions157