Rodrigues Night Heron

The Rodrigues night heron was robust, its bill was comparatively large, stout and straight, and its legs were short and strong, and more robust than those of the related Mauritius night heron. There was marked sexual dimorphism in the Rodrigues night heron, which is also present in the black-crowned night heron, and the male was the largest. There is a 17.5% length difference in the tibiotarsus between male and female specimens, 9.3% difference in the tarsometatarsus, and a 9.1% difference in the available mandibles. The difference was almost the same in the Mauritius night heron, and there was little dimorphism in the Réunion night heron. The Rodrigues night heron is estimated to have been 60 cm (24 in) long. Measurements of the bones available by the late 19th century show that the skull was 154 mm (6.1 in) long, the upper mandible was 94 mm (3.7 in) long and 22 mm (0.87 in) wide at the base, and the lower mandible was 147 mm (5.8 in) long. The sternum was 64–88 mm (2.5–3.5 in) long, the scapula 72 mm (2.8 in), the coracoid 59–67 mm (2.3–2.6 in), the humerus 118–180 mm (4.6–7.1 in), the ulna 121 mm (4.8 in), the radius 117 mm (4.6 in), and the metacarpal 62–98 mm (2.4–3.9 in). The pelvis was 63 mm (2.5 in) long, the femur 90–92 mm (3.5–3.6 in), the tibiotarsus 140–210 mm (5.5–8.3 in), the tarsometatarsus 95–162 mm (3.7–6.4 in), and the second phalanx bone 20 mm (0.79 in). …

Little is known about the behaviour of the Rodrigues night heron apart from the two contemporary descriptions, but it was better documented that its Mauritius relative. Leguat's 1708 description reads as follows, referring to these birds as "bitterns":

We had Bitterns as big and as fat as capons. They are tamer and more easily caught than the 'gelinotes' [Rodrigues rails]... The lizards often serve as prey for the birds, especially for the Bitterns. When we shook them down from the branches with a pole, these birds ran up and gobbled them down in front of us, in spite of all we could do to prevent them; and even if we only pretended to do so they came in the same manner and always followed us about. The "lizards" mentioned were probably geckos of the genus Phelsuma (there were six gecko species on Mauritius), such as the now extinct Rodrigues day gecko, which reached 23 cm (9.1 in) in length. Leguat and his companions were fond of these quite tame lizards, letting them feed from their tables, and therefore tried to protect them from the aggressive herons. …