Blue is a rarely occurring hue in nature, especially when it comes to the animal kingdom. While some may argue that the sky and ocean are examples of blue in nature, they only appear blue to us, not actually possessing the colour. Surprisingly, the sky and ocean’s blue appearance is a consequence of how their constituent particles interact with sunlight, rather than being inherently blue.
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The sky is composed of various gases and molecules that lack colour. However, these molecules scatter blue light more effectively due to its shorter wavelength compared to red light, which has a longer wavelength. As a result, the sky appears blue to us.
In the case of the ocean, water itself is colourless. However, the depths of the ocean appear blue because the water absorbs the red portion of the light spectrum and reflects blue light. Consequently, blue light prevails throughout the ocean’s expanse. This explanation leads to the question of the relevance of endangered blue animals.
Similar to the sky and ocean, most animals on the endangered blue list acquire their blue colour through interactions with light. In reality, they lack true blue pigmentation. Instead, they employ structural colouration, utilizing a physical phenomenon called iridescence. Hence, their visual appearance primarily depends on how we perceive them rather than any actual blue pigment present.
Structural Coloration and Iridescence In Blue Animals
Structural colouration is a fascinating phenomenon found in animals, plants, and some species of plankton. Through a unique evolutionary process, these organisms have developed outer surfaces that feature microscopic pores capable of interfering with light waves. The result is a colouration that reflects only the blue end of the colour spectrum.
This type of colouration often leads to iridescence, which is responsible for the differential dispersion of light as it hits the skin and feathers of these structurally coloured animals. With its stunning visual effects, it’s no wonder that scientists have been studying structural colouration for years.
Most Endangered Blue Animals
Despite the fact that some of these animals were not always rare in nature, human activities such as logging, trophy hunting, wildlife pet trading, and commercial fishing, have quickly diminished their populations. Unfortunately, this is only one part of the problem, as factors like climate change and lack of genetic diversity also play a role in the reduction of their populations. Thankfully, the IUCN [International Union for Conservation of Nature] is stepping in to classify these animals as threatened or near threatened and is continuously working towards finding ways to help preserve these species.
1. Electric Blue Gecko (Lygodactylus williamsi)
The Tanzanian blue gecko, also known as the electric blue gecko, is a species endemic to a small area of Tanzanian forest, primarily found on screwpine trees. Despite its name, the electric blue gecko does not possess the ability to generate electricity. Rather, its name reflects the striking vibrancy of its blue colouration.
This species displays a strong fidelity to a single territory, which unfortunately continues to shrink in size. This habitat loss is a significant factor contributing to the rapid decline of the blue gecko population, resulting in its critically endangered status.
The dominant males of this species exhibit bright blue colouration with black throat stripes and orange underbellies. In contrast, the females display a more bronze-brown to green hue and lack throat stripes.
Blue geckos are very small in size, reaching a maximum length of 2-3 inches when fully mature. However, their notably long tails enable them to be agile runners and gliders, enhancing their mobility.
Protecting the habitat and addressing the habitat loss of these unique geckos is crucial to their conservation and survival.
2. Blue Glaucus (Glaucus atlanticus)
The blue glaucus, also known as the blue sea slug or blue sea dragon, is a nudibranch—a soft-bodied gastropod mollusc—found in the pelagic zones of temperate seas and oceans worldwide.
Lacking any appendages for movement, these creatures rely on a gas-filled sac in their stomachs to assist in floating across the ocean’s surface. Like most nudibranchs, the blue glaucus is hermaphroditic, with both individuals capable of laying eggs after mating.
Despite their small size, blue glaucus nudibranchs possess potent venom. Interestingly, they do not produce this venom themselves but acquire it from feeding on a Portuguese man of war, a venomous hydrozoan. The blue glaucus is immune to the hydrozoan’s venom, enabling it to ingest and store the nematocysts (stinging cells) of the man o’ war in its finger-like cerata. It utilizes this venom for hunting other prey and defending itself against potential predators.
Listed as endangered by the IUCN, the blue glaucus faces population decline primarily due to factors such as pollution, ocean acidification, and the pet trade. Efforts are being made to protect and conserve this floating blue animal in order to ensure its survival.
3. Tahitian Lorikeet (Vini peruviana)
The blue lorikeet, also known as the Tahitian blue lorikeet, is an appealing and fascinating species of parrot. Found in the South Pacific, the blue lorikeet measures just 18cm long and boasts a vivid mix of dark blue plumage with white colouring on its chest, face, and throat. As an arboreal bird, the blue lorikeet can be found roosting on coconut palm trees, usually in a flock.
Their primary source of nutrition is from nectar and pollen, but they also consume bay cedar, mulberries, and occasionally tiny insects. Despite their captivating beauty, the species is in danger, classified as vulnerable by the International Union for Conservation of Nature (IUCN). This decline in population is largely due to the introduction of invasive plants and species which compete with the blue lorikeet for resources.
4. Blue Morpho Butterfly (Morpho melaneus)
The blue morpho butterfly is exclusively found in the tropical rainforests and savannahs of Central and South America, particularly in the Amazon Forest and Cerrado savannah of Brazil.
Boasting an impressive wingspan of 5 to 8 inches, it holds the distinction of being the largest butterfly in the Morpho genus, which comprises over 30 species. In fact, it is considered one of the largest butterflies in the world across all species. The blue morpho primarily sustains itself by feeding on decaying fruits and nectar found near the forest floor, and it lays its eggs on the undersides of low-growing plants.
The M. morpho butterfly possesses an incredibly ingenious use of iridescent colours among butterflies. Its dorsal wings display a vibrant blue hue with distinctive black edges, while the underside features a contrasting brown colour adorned with prominent eyespots.
This blue-brown colouration creates a fascinating visual effect, as the blue morpho butterfly appears to vanish and reappear as it flutters through the air. When at rest, the eyespots on the underside of its wings serve as a deterrent to potential predators, making the butterfly appear more intimidating.
Although the blue morpho butterfly is preyed upon by frogs, lizards, and birds in its natural habitat, the primary threats to its survival stem from deforestation and capture for private collections. These factors contribute to the endangerment of this remarkably beautiful blue creature.
5. Blue American Lobster (Homarus americanus)
The inclusion of the Blue American lobster in this list is a topic of debate due to the fact that members of the H. Americanus species typically exhibit red colouration. Additionally, the entire species is considered to be of least concern by the IUCN, further diminishing the significance of the blue animal variation.
However, the blue American lobster still merits mention due to its extreme rarity in nature. The chances of encountering a blue lobster in the wild are estimated to be as low as 1 in 2 million, and the likelihood of catching one is even more minuscule, at approximately 1 in 200 million.
Consequently, blue lobsters are exceptionally rare in their natural habitat and are predominantly observed in aquariums and conservation facilities. The distinct blue colouration of these lobsters is attributed to a genetic mutation that results in an overproduction of a protein, which combines with their natural red pigment, Astaxanthin, to form a blue animal compound called Crustacyanin.
While red lobsters are commonly found and are often sold as a prized delicacy, blue lobsters that are caught alive are typically either placed in aquariums or released back into the ocean due to their rare status.
6. Spix’s Macaw (Cyanopsitta spixii)
The Spix’s macaw, named after the German naturalist Johann Baptiste Von Spix who discovered it in 1819, holds the title of being the rarest macaw species. With a population of just over 200 individuals remaining, it is classified as critically endangered by the IUCN.
Originating from the tropical forests of Brazil, this macaw species displays a striking blue colouration that has captured the imagination of many. In fact, it served as the inspiration for the lead character in the 2011 Hollywood animated film “Rio,” which proved to be so popular that a sequel was released in 2016.
Through selective and captive breeding efforts, conservationists have managed to reintroduce the Spix’s macaw back into the Brazilian forests. In the wild, these birds typically form small family groups and forage together, feeding on fruits, nuts, and seeds. When fully grown, they can reach a length of 56cm and weigh up to 320g.
These non-migratory birds are sedentary in nature and have a lifespan that ranges from 25 to 40 years. They possess impressive mimicry skills, often imitating the songs of other birds and even human speech.
The primary threat to the existence of the Spix’s macaw is the illegal capture and trade for private pet keeping. Since they are social creatures, they do not thrive well when kept alone in captivity, which has contributed to their dwindling population. Efforts are being made to combat this illegal trade and protect the remaining individuals in the wild.
7. Blue Iguana (Cyclura lewisi)
The blue iguana, also referred to as the Grand Canyon rock iguana, is a lizard that can only be found on the Grand Cayman Islands. Despite its name, this reptile does not possess any inherent blue skin pigmentation. Instead, its colours vary between males and females, with males displaying turquoise blue to dark grey hues, while females exhibit pale blue to olive green tones.
What makes the blue iguana truly fascinating is its ability to reflect blue colours through a unique crystal cell structure in its skin. This structural colouration serves various purposes, including signalling different moods and behaviours. Notably, the blue animals colour becomes most prominent during the breeding season, from April to June, indicating the lizard’s readiness to mate.
Upon reaching maturity, this solitary herbivore can grow up to 150cm in length and weigh up to 15 kg. However, despite its size, the blue iguana remains vulnerable to predators such as dogs and feral cats, which hunt it as prey.
These iguanas prefer lowland grasslands that are in close proximity to a water source, allowing them easy access to feed on flowers, fruits, and leaves, often within reach of trees.
8. Congo Peafowl (Afropavo congensis)
Originating from the Congo lowland forests in Africa, this particular species represents one of the three surviving types of peafowls, with its counterparts being the Indian and Indonesian peafowl, which are more recognizable to most people due to their extravagant long feathers. However, the African Peafowl possesses its own distinctiveness, compensating for its lack of flamboyance.
In comparison to other peafowl species, the Congo peafowl is smaller in size, has a shorter tail, and lacks the vibrant Ocelli, which are the multi-coloured eye spots found on the feathers of its Asian relatives. Instead, its feathers resemble those of a young Asian peafowl, lacking the full splendour of mature plumage.
The feathers of the African peafowl exhibit a deep blue colouration with hints of green and violet, a result of selective structural colouration. However, the female peahens possess noticeably less blue in their plumage.
As omnivores, these blue animals consume a varied diet consisting of seeds, fruits, insects, amphibians, and small reptiles within their limited geographic range.
Furthermore, conservationists have classified this species as vulnerable, and its population decline can be attributed to the loss of habitat caused by agricultural activities, mining operations, and logging in the Congo Basin and surrounding areas.
9. Antarctic Blue Whale (Balaenoptera musculus)
With astounding lengths reaching up to 30 meters and weighing a staggering 200 tons, the Antarctic blue whale holds the remarkable distinction of being the largest recorded creature in both sea and land history. It surpasses even the colossal African elephant, the largest land-dwelling animal, and exceeds the size of the colossal prehistoric dinosaurs.
The blue whale’s distinct blue colouration is predominantly visible underwater, possibly due to the enhanced visibility of blue light in aquatic environments. However, when these magnificent creatures surface to breathe, they exhibit a greyish-blue appearance.
Despite their gargantuan stature, the feeding behaviour of the Antarctic blue whale is intriguing. They are discerning eaters, primarily relying on krill—a type of small crustacean that congregates in vast swarms—as their main food source. Occasionally, they may also include tiny fish and copepods in their diet.
In contrast to other apex predators in the marine ecosystem, such as killer whales or sperm whales, the blue whale lacks teeth. Instead, it possesses bristly baleen plates, which it employs as a filtering mechanism to sift seawater while hunting for krill.
As mammals, blue whales exhibit parental care and nurse their offspring with milk after giving birth. They are primarily solitary creatures and display high levels of monogamy in their mating habits, employing loud vocalizations to communicate and locate potential mates and other nearby blue whales.
Despite inhabiting regions spanning the southern hemisphere from Antarctica to Australia and New Zealand, the blue whale remains endangered, primarily due to historical commercial whaling activities that drastically reduced their population.
10. Blue Crane (Grus paradise)
Also referred to as the Stanley crane or paradise crane, this terrestrial bird is exclusive to the southern region of Africa. The majority of its population is concentrated in South Africa, although a few blue cranes can be found in neighbouring countries such as Namibia, Zimbabwe, and Botswana.
This may be one reason why the blue crane has been designated as the national bird of South Africa. Moreover, the blue crane holds cultural significance for many local tribes in the country, and local conservationists are actively working to enhance its vulnerable status on the IUCN Red List.
Unlike many other crane species, the blue crane does not embark on long-distance migrations for breeding or feeding purposes. Instead, it is an altitudinal migrant, typically nesting and foraging in high-altitude grasslands. However, during winter, these birds descend to lower-altitude areas with warmer temperatures.
The mating behaviour of the blue crane involves an intricate courtship ritual, and both parents take part in guarding and incubating their eggs until they hatch. Typically, the number of eggs laid by this species is limited to two, as deviations from this range are uncommon. Once mature, blue cranes can reach a height of up to 120cm and have a wingspan of 200cm.
Additionally, the blue crane’s feeding habits are variable and dependent on the proximity and availability of food resources. It can adapt to a herbivorous or carnivorous diet as required.
What animals have the colour blue?
Some examples of animals with a predominantly blue physical appearance include blue jays, blue butterflies, blue whales, and blue-tongued skinks. The blue morpho butterfly is particularly known for its striking metallic blue wings, which serve as its primary defence mechanism in the wild.
What mammals have blue?
Although its skin appears mostly grey, when viewed in certain lighting conditions, a blue tint can be detected. Another mammal with blue is the mandrill, a type of primate found in the rainforests of Africa. Male mandrills possess bright blue markings on their faces which act as a visual cue during social interactions. Lastly, the blue-tongued skink, a lizard native to Australia, has a distinctive blue tongue used for deterrence and attracting mates.
What is the rarest blue animals?
The blue-ringed octopus, native to the waters of the Pacific and Indian Oceans, stands out as one of the most striking creatures in the underwater world. Despite its small size, it packs a potent and deadly venom that makes it one of the ocean’s most dangerous inhabitants. With its bright blue rings, this octopus is not only rare but also fascinating and a reminder of how nature can surprise us with its stunning beauty and hidden dangers.
Final Words on Blue Animals
Among the most affected creatures are blue animals, whose numbers continue to dwindle as a result of several different factors. However, the good news is that learning about these blue animals and their struggles can help us develop an understanding of the issue at hand and find ways to prevent it.
If you found this topic intriguing, there is still more exciting information to be discovered. This article will take you on a journey through the world of black and white animals and showcase the beauty and uniqueness of these remarkable creatures.
Growing up enjoying the beauty of my village, a good passion for nature developed in me from childhood. Following my passion for the natural world, I have chosen zoology for my graduation, during my undergraduate degree, I participated in many nature trails, bird watching, rescues, training for wildlife conservation, workshop, and seminars on biodiversity. I have a keen interest in invertebrate biology, herpetology, and ornithology. Primary interests include studies on taxonomy, ecology, habitat and behavior.