An expedition to Christmas Island
Henry N. Ridley, a senior botanist at the Singapore Botanic Gardens, published this account of a September–October 1904 expedition to Christmas Island, a small coral-and-basalt island in the Indian Ocean then under active phosphate mining. Accompanied by the zoologist Dr. Hanitsch and a small team of collectors, Ridley produced a detailed field survey of the island’s flora and fauna across its distinct ecological zones.
Summary
The article reads as a day-by-day field journal documenting systematic botanical and zoological collection across Christmas Island’s varied terrain—from the seashore terraces and coral pinnacles of Flying Fish Cove, through the plateau forest, to the phosphate quarries and the inaccessible western cliffs. Ridley’s primary interest is botanical, and he records numerous new additions to the island’s flora, including a species of Balanophora (a parasitic plant previously unrecorded from any oceanic island), Spondias (a Hog plum characteristic of Polynesian islands), and various grasses, orchids, and coastal shrubs. He also maps the distinct zonation of vegetation: the seashore trees (Guettarda, Gyrocarpus, Pisonia) giving way to the plateau forest (Eugenia, Barringtonia, Cryptocarya, Sideroxylon), with freshwater streams supporting yet another assemblage of species.
The narrative is interspersed with observations on the phosphate mining operations—the tram lines, quarries, coolie lines, and the felling of trees for excavation—which Ridley records with a botanist’s eye for how introduced weeds were spreading up the hill on workers’ clothing. A significant portion of the article is devoted to a failed attempt to cross the island over Murray Hill to the west coast, where the party reached the top of the upper terrace near Egeria Point before being forced to retreat due to exhaustion of their water supply. Ridley also documents the fauna encountered, including the abundance of the large pigeon Carpophaga, nesting boobies, the robber crab Birgus latro (which repeatedly invaded their tents at night), and a feral cat that had escaped from European ownership.
The article serves as a baseline ecological record of Christmas Island at a moment of significant environmental transformation, capturing the island’s biodiversity before phosphate mining had progressed further into the interior.
Key Findings
- The expedition departed Anjer (Java) on 20 September 1904 aboard the S.S. Islander and reached Christmas Island on 25 September; the party included Dr. Hanitsch, taxidermists De Fontaine and Ahwang, plant collector Kassan, and two boys (p. 137).
- Ridley recorded a species of Balanophora growing on the shore terrace near the Waterfall, noting it was “not recorded from any oceanic Island previously” (p. 146).
- A species of Spondias (Hog plum), characteristic of Polynesian islands, was found at Andrews’ Lookout on the North East Point cliff; the fallen fruit lay untouched by any bird or bat, suggesting no effective seed-disperser existed on the island (p. 141).
- The Murray Hill crossing expedition (17–20 October) covered approximately 15 miles before the party was forced to retreat due to water exhaustion; they reached the top of the upper terrace near Egeria Point, a location “never yet reached by anyone as far as is known” (pp. 150–153).
- The robber crab Birgus latro was so abundant during the Murray Hill camp that it repeatedly entered the tents, stealing a saucepan, a boot, a killing bottle, and a bottle of quinine (pp. 151–153).
- A feral yellow tabby cat, escaped from a European owner, was captured near the Waterfall; Ridley noted that while Andrews had deprecated the introduction of cats for fear they would destroy seabirds, the terrestrial birds (ground pigeon, thrush, whiteeye) were actually more vulnerable (p. 149).
Conclusion
Ridley’s account establishes a detailed ecological baseline for Christmas Island at the height of its early phosphate mining phase, documenting the island’s distinctive zonation of flora and fauna while simultaneously recording the incipient impacts of mining operations—tree felling, weed introduction, and habitat disturbance. The article’s lasting value lies in its precise observations of species distributions and the identification of several taxa new to the island’s recorded flora, providing a reference point against which subsequent environmental change could be measured.
Context
- Ridley was a senior botanist at the Singapore Botanic Gardens; the expedition was undertaken in his professional capacity, and the article was published in the journal of the Straits Branch of the Royal Asiatic Society, the learned society of the Straits Settlements colonial administration.
- The article is a first-hand field report drawing on no archival sources. Its historiographical contribution is as a primary ecological record of Christmas Island circa 1904, predating the island’s later environmental degradation.