Arachnocampa luminosa, the fungus gnat endemic to New Zealand, spins a hammock of silk threads tipped with sticky mucus droplets, then emits a cold blue-green light to lure prey into its snare. The larva glows brightest when hungry, and the limestone overhangs and fern-draped caves around Rotorua provide the damp, sheltered darkness the species requires. These geothermal lakeshores have hosted glow worm populations for millennia, but paddlers began exploring them by kayak only in the early 2000s, when local Māori operators and adventure outfitters recognized that silent, low-impact boats offered the clearest view of the bioluminescent colonies without disturbing the delicate larvae. Lake Rotorua and Lake Rotoiti, both calderas shaped by volcanic collapse, sit within the Rotorua Caldera, a geothermal system that feeds hot springs, fumaroles, and mineral-rich tributaries along their shores. The lakes' sheltered bays and stream inlets create microclimates where humidity and temperature remain stable year-round, allowing glow worm colonies to thrive in densities rare elsewhere in the North Island. Okere Falls, at the outlet of Lake Rotoiti, channels water through a narrow basalt gorge lined with overhanging rock ledges and native bush; the mist from the falls and the acoustic dampening of the forest make this stretch one of the most productive glow worm habitats accessible by kayak. Operators launch at dusk, timing arrivals to coincide with the larvae's peak luminescence as twilight deepens and the insects intensify their glow to compete for nocturnal prey. The Rotorua glow worm kayak tour industry is largely Māori-led, with Te Arawa iwi descendants guiding many of the twilight paddles. These operators incorporate cultural narratives about the lakes' formation, the significance of geothermal activity in local tradition, and the ecological role of native species like koura (freshwater crayfish) and kākahi (freshwater mussels) that share the waterways with glow worms. Tours depart from Okere Falls Road and follow routes that pass beneath limestone bluffs, through narrow stream channels, and into shallow bays where the absence of artificial light allows the bioluminescence to dominate the visual field. As of 2026, the activity has grown to include hot springs stops on Lake Rotoiti routes, where paddlers can swim in geothermally heated inlets before returning to view the glow worms on the return leg. The combination of geothermal and bioluminescent phenomena in a single paddle route remains unique to this caldera system, and the tours have become a benchmark for low-impact nocturnal ecotourism in New Zealand.