Gary Bell/ Oceanwide / Sea Lettuce (Ulva australis) and other alga, Hopkins Island, South Australia, Australia

Mark Carwardine / New Zealand robin (Petroica australis) male, ringed by researchers, South Island race, Ulva Island, Paterson Inlet, Stewart Island, South Island, New Zealand, June

Mark Carwardine / New Zealand robin (Petroica australis) male, ringed by researchers, South Island race, Ulva Island, Paterson Inlet, Stewart Island, South Island, New Zealand, June

Brent Stephenson / Crown fern (Blechnum discolor) with new unfurling fronds developing, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Wheki / Rough tree fern (Dicksonia squarrosa) frond unfuling, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Greenhood orchid (Pterostylis auriculata) close up of flower, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Greenhood orchid (Pterostylis auriculata) flower, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Rimu (Dacrydium cupressinum) close up of young leaves, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Dancing spider orchid (Corybas acuminatus) flowering, amongst mosses on the forest floor, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / New Zealand spider orchid (Corybas oblongus) in flower, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / New Zealand spider orchid (Corybas oblongus) flower, Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Adult Red-crowned parakeet (Cyanoramphus novaezelandiae) foraging on totara (Podocarpus) fruits in the sub-canopy. Ulva Island, Stewart Island, New Zealand, February.

Brent Stephenson / Adult male Yellowhead (Mohoua ochrocephala) hanging on the side of a tree fern whilst foraging. Ulva Island, Stewart Island, New Zealand, February. Endangered species.

Brent Stephenson / Adult New Zealand kaka (Nestor meridionalis) feeding on fresh buds of tree daisy (Olearia). This is the Southern subspecies, meridionalis. Ulva Island, Stewart Island, New Zealand, November. Endangere...

Brent Stephenson / Weka (Gallirallus australis scotti) chick amongst leaflitter on the forest floor. The adult was nearby. Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Recently fledged juvenile South Island saddleback (Philesturnus carunculatus) peering out from the undergrowth. Ulva Island, Stewart Island, New Zealand, November.

Brent Stephenson / Adult South Island saddleback (Philesturnus carunculatus) foraging on nectar of the Southern rata (Metrosideros umbellata) Ulva Island, Stewart Island, New Zealand, November.

Mike Read / Red crowned parakeet (Cyanoramphus novaezelandia / saisseti) Ulva Island, New Zealand

Brent Stephenson / Weka (Gallirallus australis) walking along a sandy beach. Ulva Island, Stewart Island, New Zealand.

Pete Oxford / Marine Iguana (Amblyrhynchus cristatus) feeding on Sea Lettuce (Ulva sp), Santiago Island, Galapagos Islands, Ecuador

Pete Oxford / Marine Iguana (Amblyrhynchus cristatus) feeding on Sea Lettuce (Ulva sp), Santiago Island, Galapagos Islands, Ecuador

Pete Oxford / Marine Iguana (Amblyrhynchus cristatus) feeding on Sea Lettuce (Ulva sp), Santiago Island, Galapagos Islands, Ecuador

Mike Potts / New zealand robin {Petroica australis} with tags, Ulva Island, South Island, New Zealand

Mike Potts / Variable Oystercatcher {Haematopus unicolor} Ulva Island, South Island, New Zealand

Mike Potts / Bellbird {Anthornis melanura} searching for food on beach, Ulva Island, South Island, New Zealand

Mike Potts / Weka {Gallirallus australis} feeding on rocky shoreline, Ulva Island, South Island, New Zealand

Mike Potts / Tui / Parson bird {Prosthemadera novaeseelandiae} Ulva Island, South Island, New Zealand

Mike Potts / Tui {Prosthemadera novaesellandiae} Ulva Island, South Island, New Zealand

Michael & Patricia Fogden / Weka (Gallirallus australis), Ulva Island, Stewart Island, New Zealand

Michael & Patricia Fogden / Weka (Gallirallus australis) flightless bird endemic to New Zealand, Ulva Island, New Zealand

Michael & Patricia Fogden / Weka (Gallirallus australis) flightless bird endemic to New Zealand, Ulva Island, New Zealand

Gary Bell/ Oceanwide / Sea Sweep (Scorpis aequipinnis) in Sea Lettuce (Ulva australis), Hopkins Island, South Australia, Australia

Doug Gimesy / Ulva Island as seen from Stewart Island, New Zealand, Pacific Ocean, January, 2023.

Mike Read / View of Ulva Island with low clouds over south western edge of Isle of Mull. Inner Hebrides, Argyll and Bute, Scotland, UK. May.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus), grazing Ulva algae on lava seafloor, Fernandina Island, Galapagos, South America, Pacific Ocean.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) swimming back to share food after grazing Ulva algae on lava seafloor, Fernandina Island, Galapagos, Pacific Ocean, South America.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) grazing Ulva algae on lava seafloor, Fernandina Island, Galapagos, Pacific Ocean, South America.

Tui De Roy / Marine iguana (Amblyrhynchus cristatus) grazing Ulva algae on lava seafloor, Fernandina Island, Galapagos, Pacific Ocean, South America.

David Hall / Split-level of Cormorants (Phalacrocorax sp.) standing on rocks with Sea lettuce (Ulva sp.) seen underwater, Hussar Bay, Nigei Island, Queen Charlotte Strait, British Columbia, Canada. September.

David Hall / Split level shot of kelp and other 'seaweeds' partly exposed at low tide, with coniferous forest in the background. Seen in this photograph are the following: Turkish washcloth (Mastocarpus pa...