Several archaeological sites contain a number of recorded cultural values. These include at least 349 known culturally modified trees (CMTs), remnants of carved canoes, a fish weir, test hole trees, notched logs and tapered bark strips. Many of these areas have not been inventoried thoroughly which indicates that the conservancy likely contains many other unrecorded cultural heritage and archaeological sites.
Kiidk’yaas, also known as the “golden spruce”, grew on the bank of the Yakoun River. The site is tied to ancient Haida stories and was locally significant to many inhabitants of Haida Gwaii. This genetically rare tree was cut down in 1997. A short well-maintained trail leads from the parking area through old-growth forest to the bank of the Yakoun River overlooking where the Golden Spruce once stood.
Yaaguun G̱andlaay is one of the most important Haida food fish gathering sites on Haida Gwaii.
The conservancy is underlain by undivided sedimentary rocks. The surficial geology is made up of coarse textured morainal deposits over plains and gentle slopes in the upland areas and fine textured fluvial material and some coarser deposits along the valley bottoms. Yaaguun G̱andlaay Conservancy is situated at the mouth of the Yakoun River, the largest river drainage on Haida Gwaii. The estuary is dominated by warm shallow, sandy and flat bottom physiography typified by low current and low exposure.
It contains some of the most productive forests on Haida Gwaii with over half in old growth condition. Slender-spiked mannagrass and angled bitter-cress are locally rare species that occur within the area.
Yaaguun G̱andlaay Conservancy is the only estuary on Haida Gwaii that serves as habitat for all coastal salmon species. Florence Creek, Canoe Creek and the Yakoun River are fish-bearing with the latter hosting chinook salmon (wild and augmented), chum salmon, coho salmon, (wild and augmented), coastal cutthroat trout, eulachon, pink salmon, sockeye salmon, steelhead, aleutian sculpin, prickly sculpin, threespine stickleback, river lamprey and Western brook lamprey. Steelhead and Dolly Varden are also found in the area. This estuary contains important habitat for eelgrass and juvenile salmon.
The cultural heritage values in the heritage site/conservancy include opportunities for the ongoing continuance of Haida culture through traditional use of the area. Some examples of traditional use within Yaaguun G̱andlaay Conservancy may include monumental cedar and cedar bark harvesting, medicinal plant harvesting, hunting, fishing, trapping and food gathering. The conservancy also provides a place for the physical expression of culture through monumental art such as totems or establishment of traditional style infrastructure such as longhouses.