Accessible by boat, but no docking facilities.

See the complete PDF from BC PARKS: Trial Islands ER 132

Physical:  The reserve comprises parts of two elongate rocky islands and associated islets. Marine waters are not included. Shorelines on the southwest side are mostly steep and dissected but the rest of the shoreline is gently sloping with a few small pocket beaches, comprised mostly of gravel. The islands are of considerable interest for the interpretation of local and regional geology, being situated at or adjacent to a major suture between two crustal blocks, the Leach River Complex and Wrangellia Terrane. Soil cover is thin and incomplete on much of the island, consisting mostly of Brunisols lying on bedrock. Small areas of Regosolic soils and considerable exposed bedrock are present. The climatic regime here is the mildest in the province, and characterized by frequent wind and summer drought.
Biological:
Twenty-eight species of vascular plants listed as rare in British Columbia are
present in the reserve, 15 of which are in the categories of greatest rarity in the
province. The latter are mostly plants of a more southerly distribution, centred in northern California and in Oregon, and are at or near the northern limit of their range in the Victoria area. Many were once scattered along the Victoria waterfront prior to urbanization but are now found in only a few sites outside of the Trial Islands.
Shallow soils, summer drought and strong winds combine to prevent tree growth on these islands. Plant communities consist of herbaceous meadows, shrub thickets and sparse growth of lichens and other plants on bedrock.
Nine plant communities have been described. Two are dominated by lichens growing on bedrock, but contain other dry-site plants like stonecrops and a few species tolerant of salt spray. A community characterized by dune wildrye and  beach pea occurs on gravel beaches and among driftwood. A small area of salt  marsh contains salt-tolerant plants like Pacific glasswort, seashore saltgrass, Nutka alkaligrass and sea plantain. Four meadow communities occur on upland sites having the best soil development. The most important of these, a vernal pool community characterized by Bigelow’s plantain and Scouler’s popcornflower, contains 13 species of rare plants. Other meadow communities support showy stands of spring wildflowers such as common camas, death-camas, chocolate lily, shootingstar, sea blush, Hooker’s onion and blue-eyed Mary. Dense, wind-pruned
shrub thickets are dominated by Garry oak, aspen, snowberry and rose.One glaucous-winged gull nest has been reported, but the island is not a significant seabird site. A turkey vulture nest was found in the early part of the century (mid- 2000s) but it has not been occupied since. Terrestrial birds and mammals have not been surveyed.
Cultural: The reserve encompasses a traditional First Nations and Songhees bulb harvesting site. There are no known archaeological sites on the islands.
The island has been the site for a lighthouse for over a century.

Hooker’s Onion

Threat of oil spill due to tanker traffic and cargo ships