Basking shark vs Common Water Rat

Rhincodon typus compared with Hydromys chrysogaster

Key Differences

• Basking shark is Endangered while Common Water Rat is Least Concern.

Taxonomic Classification

Rank	Basking shark	Common Water Rat
Kingdom same	Animalia (Animals)	Animalia (Animals)
Phylum same	Chordata (Chordates)	Chordata (Chordates)
Class	Chondrichthyes (Cartilaginous Fish)	Mammalia (Mammals)
Order	Lamniformes (Mackerel Sharks)	Rodentia (Rodents)
Family	Rhincodontidae (Whale Sharks)	Muridae (Mice & Rats)
Genus	Rhincodon (Whale Sharks)	Hydromys
Species	Rhincodon typus	Hydromys chrysogaster

Evolutionary Relationship

Basking shark and Common Water Rat share a common ancestor at the Phylum level: Chordata. (Chordates)

Conservation Status

Basking shark

EN — Endangered

Trend: Decreasing ↓

Common Water Rat

LC — Least Concern

Physical Characteristics

Attribute	Basking shark	Common Water Rat
Diet	Omnivore	—
Average Lifespan	100 years	—
Average Length	12.0 m	—
Average Weight	20.0 t	—

Habitat & Geographic Range

Basking shark

Habitat

Found across multiple habitat types including temperate broadleaf and mixed forests, temperate grasslands and steppes, and montane grasslands and shrublands, among 5 distinct biome types within the Neotropic biogeographic realm.

Range

Distributed across Chile, Portugal, Taiwan, and Venezuela. Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Common Water Rat

Habitat

Typically found in diverse terrestrial and aquatic ecosystems.

Basking shark

The world's largest fish, whale sharks can exceed 12 meters and 20 tonnes, inhabiting tropical and warm temperate oceans worldwide. Despite their massive size, they are harmless filter feeders, consuming plankton, fish eggs, and small fish by swimming open-mouthed through prey-dense water. They undertake vast seasonal migrations following plankton blooms. Endangered due to fishing, boat strikes, and the live fin trade, with population declining by approximately 50% over the past 75 years.

Common Water Rat

<em>Hydromys chrysogaster</em>, commonly known as the common water rat or rakali, is a semi-aquatic rodent in the family Muridae, native to Australia and New Guinea. It is classified as Least Concern by the IUCN, reflecting its relatively stable population across a broad range of freshwater and estuarine habitats on the Australian continent and associated islands. The species typically inhabits the banks of rivers, lakes, wetlands, and estuaries, where it constructs burrows in streambanks. It is highly adapted for an aquatic lifestyle, with partially webbed hind feet, a flattened head, and a dense waterproof coat. <em>Hydromys chrysogaster</em> is a carnivore, typically feeding on fish, crustaceans, mussels, frogs, and aquatic invertebrates, which it often carries to elevated feeding platforms to consume. The species is nocturnal and crepuscular, most active during early morning and evening hours near the water's edge. Biological traits including average lifespan, body length, and weight remain poorly documented in standardized databases, though adults are generally robust for a rodent, reportedly reaching body lengths of 20–35 cm excluding the tail. Geographic range details for this particular record remain incompletely documented in available data sources. Ecologically, the common water rat is an important apex predator in small-scale freshwater food webs and serves as an indicator species for wetland health in Australian riparian systems.