--- title: "Asian Water Monitor (Varanus salvator) | AnimalTracks.wiki" description: "A semi-aquatic lizard that can reach 2.5 m, scent a rotten carcass up to 100 m away and prey on any vertebrate it can overpower." image: "https://animaltracks.wiki/images/animals/asian-water-monitor-1.webp" published: "2026-10-11" updated: "2026-10-11" --- # Asian Water Monitor (*Varanus salvator*) > **Status**: Checked against 5 sources, listed under Sources below. > **Tagline**: A semi-aquatic lizard that can reach 2.5 m, scent a rotten carcass up to 100 m away and prey on any vertebrate it can overpower. > **Soundtrack Vibe**: Krautrock & Electronic Pioneers // NEU!, "Isi" > **Soundtrack Links**: [Spotify](https://open.spotify.com/track/2Tlz08BqB9bUeVJZVcPd2v) > **Vibe Match**: On a treadmill a water monitor kept up a pace that needed 85% of its maximum oxygen use for 45 minutes. Isi runs on the motorik beat, one steady drum pattern held without a break for the length of the track. ## Biological Superpowers & Stats - **Taxonomy**: *Varanus salvator* - **Danger Level**: Medium - **Conservation Status**: Least Concern ([IUCN Red List](https://doi.org/10.2305/iucn.uk.2021-2.rlts.t178214a113138439.en)) - **Superpower**: Follows scent trails and can smell a rotten carcass from up to 100 m away - **Habitat**: Southern and Southeast Asia, near beaches, mangrove swamps, lakes, streams and rivers - **Diet**: Insects, crabs, fish, freshwater turtles, birds and their eggs, rats, other lizards and carrion - **Tags**: reptile, wetlands, carnivore ## Natural History & Behavior ## A Nose That Reads the Trail The **Asian water monitor** (*Varanus salvator*) can follow a scent trail and pick up a rotten carcass from up to 100 m away, a U.S. government risk summary reports. When its genome was compared with five other reptiles, 234 gene families were specific to the water monitor. Among them, genes for vomeronasal type 2 receptors, a family tied to the response to pheromones (chemical signals that animals give off), came out as significant in the analysis. ## Southeast Asia's Biggest Monitor Scientists who sequenced its genome call it the largest monitor in Southeast Asia and the second largest lizard globally, after the Komodo dragon. It may reach a total length of 2.5 m, which is more than 8 ft. Males are typically larger than females. The AnAge database gives an average adult weight of 4,345 g. It is extremely widespread, living across southern and Southeast Asia, from eastern India, Sri Lanka and Bangladesh through Thailand and Malaysia to Indonesia and the Philippines. It prefers habitats near water: beaches, mangrove swamps, peat swamps, lakes, streams and rivers. It sleeps in burrows it digs itself and uses water and burrows to cool off in the heat of the day. > **An extremely broad diet** > Insects, crabs, fish, freshwater turtles, birds and their eggs, lizards and rats are on the menu, along with crocodiles, sea turtles and carrion. Research has found that it will also scavenge food leftovers from residents and tourists. ## A Pace It Can Hold Researchers put lizards on a treadmill. A water monitor ran for 45 minutes at a pace that needed 85% of its maximum oxygen use. For the first 10 minutes it also drew on supplementary anaerobic metabolism (energy made without enough oxygen), shown by a 16 mmol/l rise in blood lactate. Half of that lactate was cleared by the end, and its blood pH was back to resting levels. In a harder test, all three lizard species tested (the water monitor, another monitor and an iguana) were exhausted after 5 to 10 minutes. ## Eggs, Skins and Survival A clutch holds 5 to 30 eggs, and incubation lasts 171 to 327 days. Hatchlings are 250 to 390 mm long. In captivity the average lifespan is 10.6 years. The species is one of the most heavily exploited monitor lizards in the world. It is hunted mainly for its skin, used in the leather trade, as well as for its meat and its fat, used in traditional medicine. A 1999 estimate put the trade at 1.5 million skins a year, though the skin trade has decreased slightly since the 1990s. The IUCN Red List rates it Least Concern. ## Frequently Asked Questions ### Is the Asian water monitor the biggest lizard in the world? No, the Komodo dragon is. The team that sequenced the water monitor's genome puts it second among lizards worldwide. *(Source: [Chetruengchai et al. 2022]())* ### How long do Asian water monitors live? The AnAge database records 15.7 years as its maximum longevity, in captivity. *(Source: [AnAge: The Animal Ageing and Longevity Database]())* ### What do Asian water monitors eat? They prey on invertebrates and on any vertebrate they can overpower, fish included. Carrion is on the menu too. *(Source: [U.S. Fish and Wildlife Service]())* ## Sources 1. [Ecological Risk Screening Summary: Common Water Monitor (Varanus salvator). U.S. Fish and Wildlife Service.]() 2. [Varanus salvator. AnAge: The Animal Ageing and Longevity Database.]() 3. [Chetruengchai et al. (2022). Genome of Varanus salvator macromaculatus (Asian Water Monitor) Reveals Adaptations in the Blood Coagulation and Innate Immune System. Frontiers in Ecology and Evolution.]() 4. [Gleeson & Bennett (1982). Acid-Base Imbalance in Lizards During Activity and Recovery. Journal of Experimental Biology.]() 5. [Quah et al. (2021). Varanus salvator. The IUCN Red List of Threatened Species 2021: e.T178214A113138439.]() *Published October 11, 2026. Last updated October 11, 2026.* ```json { "@context": "https://schema.org", "@graph": [ { "@type": "Article", "@id": "https://animaltracks.wiki/animals/asian-water-monitor/#article", "isPartOf": { "@id": "https://animaltracks.wiki/#website" }, "headline": "Asian Water Monitor (Varanus salvator) | AnimalTracks.wiki", "description": "A semi-aquatic lizard that can reach 2.5 m, scent a rotten carcass up to 100 m away and prey on any vertebrate it can overpower.", "image": [ "https://animaltracks.wiki/images/animals/asian-water-monitor-1.webp" ], "datePublished": "2026-10-11", "dateModified": "2026-10-11", "author": [ { "@type": "Organization", "name": "AnimalTracks.wiki Editorial Team", "url": "https://animaltracks.wiki" } ], "publisher": { "@type": "Organization", "@id": "https://animaltracks.wiki/#organization", "name": "AnimalTracks.wiki", "url": "https://animaltracks.wiki", "logo": { "@type": "ImageObject", "url": "https://animaltracks.wiki/icon-512.png" } }, "mainEntityOfPage": "https://animaltracks.wiki/animals/asian-water-monitor/", "citation": [ { "@type": "CreativeWork", "name": "Ecological Risk Screening Summary: Common Water Monitor (Varanus salvator)", "url": "https://www.fws.gov/sites/default/files/documents/Ecological-Risk-Screening-Summary-Common-Water-Monitor.pdf", "publisher": { "@type": "Organization", "name": "U.S. Fish and Wildlife Service" } }, { "@type": "CreativeWork", "name": "Varanus salvator", "url": "https://genomics.senescence.info/species/entry.php?species=Varanus_salvator", "publisher": { "@type": "Organization", "name": "AnAge: The Animal Ageing and Longevity Database" } }, { "@type": "ScholarlyArticle", "name": "Genome of Varanus salvator macromaculatus (Asian Water Monitor) Reveals Adaptations in the Blood Coagulation and Innate Immune System", "url": "https://doi.org/10.3389/fevo.2022.850817", "author": "Chetruengchai et al.", "datePublished": "2022", "isPartOf": { "@type": "Periodical", "name": "Frontiers in Ecology and Evolution" }, "identifier": "doi:10.3389/fevo.2022.850817" }, { "@type": "ScholarlyArticle", "name": "Acid-Base Imbalance in Lizards During Activity and Recovery", "url": "https://doi.org/10.1242/jeb.98.1.439", "author": "Gleeson & Bennett", "datePublished": "1982", "isPartOf": { "@type": "Periodical", "name": "Journal of Experimental Biology" }, "identifier": "doi:10.1242/jeb.98.1.439" }, { "@type": "ScholarlyArticle", "name": "Varanus salvator. The IUCN Red List of Threatened Species 2021: e.T178214A113138439", "url": "https://doi.org/10.2305/iucn.uk.2021-2.rlts.t178214a113138439.en", "author": "Quah et al.", "datePublished": "2021", "isPartOf": { "@type": "Periodical", "name": "The IUCN Red List of Threatened Species" }, "identifier": "doi:10.2305/iucn.uk.2021-2.rlts.t178214a113138439.en" } ], "about": { "@type": "Taxon", "name": "Asian Water Monitor", "scientificName": "Varanus salvator", "description": "Follows scent trails and can smell a rotten carcass from up to 100 m away" } }, { "@type": "FAQPage", "@id": "https://animaltracks.wiki/animals/asian-water-monitor/#faq", "mainEntity": [ { "@type": "Question", "name": "Is the Asian water monitor the biggest lizard in the world?", "acceptedAnswer": { "@type": "Answer", "text": "No, the Komodo dragon is. The team that sequenced the water monitor's genome puts it second among lizards worldwide.", "citation": { "@type": "ScholarlyArticle", "name": "Genome of Varanus salvator macromaculatus (Asian Water Monitor) Reveals Adaptations in the Blood Coagulation and Innate Immune System", "url": "https://doi.org/10.3389/fevo.2022.850817", "author": "Chetruengchai et al.", "datePublished": "2022", "isPartOf": { "@type": "Periodical", "name": "Frontiers in Ecology and Evolution" }, "identifier": "doi:10.3389/fevo.2022.850817" } } }, { "@type": "Question", "name": "How long do Asian water monitors live?", "acceptedAnswer": { "@type": "Answer", "text": "The AnAge database records 15.7 years as its maximum longevity, in captivity.", "citation": { "@type": "CreativeWork", "name": "Varanus salvator", "url": "https://genomics.senescence.info/species/entry.php?species=Varanus_salvator", "publisher": { "@type": "Organization", "name": "AnAge: The Animal Ageing and Longevity Database" } } } }, { "@type": "Question", "name": "What do Asian water monitors eat?", "acceptedAnswer": { "@type": "Answer", "text": "They prey on invertebrates and on any vertebrate they can overpower, fish included. Carrion is on the menu too.", "citation": { "@type": "CreativeWork", "name": "Ecological Risk Screening Summary: Common Water Monitor (Varanus salvator)", "url": "https://www.fws.gov/sites/default/files/documents/Ecological-Risk-Screening-Summary-Common-Water-Monitor.pdf", "publisher": { "@type": "Organization", "name": "U.S. Fish and Wildlife Service" } } } } ] }, { "@type": "MusicRecording", "name": "Isi", "byArtist": { "@type": "MusicGroup", "name": "NEU!" }, "genre": "Krautrock & Electronic Pioneers", "url": "https://open.spotify.com/track/2Tlz08BqB9bUeVJZVcPd2v" } ] } ```