Are you interested in learning more about the Egyptian Goose?

This bird is native to Africa and has become a popular species around the world. Egyptian Geese are fascinating creatures that have unique characteristics and behaviors. In this article, we will explore ten fun facts about the Egyptian Goose that you may not know about.

1. Appearance and Physical Features

Egyptian Geese have a striking appearance with their chestnut brown feathers, distinctive eye markings, and long necks. They are medium-sized birds, with males weighing around 1.6 kg and females weighing around 1.4 kg. Their wingspan is about 1.6 meters, and their height ranges from 63 to 73 centimeters.

2. Habitat and Range

Egyptian Geese are found in a variety of habitats, including wetlands, savannas, and grasslands. They are widespread in Africa, from the Nile Valley to the southern regions of the continent. In recent years, they have been introduced to other parts of the world, such as Europe and North America.

3. Breeding Habits

Egyptian Geese are monogamous and form strong pair bonds. They mate for life and remain together year-round. They usually breed during the rainy season when the water levels rise, providing more food and shelter for their offspring.

4. Nesting Behaviors

Egyptian Geese are territorial and often defend their nests aggressively. They build their nests in a variety of locations, including trees, shrubs, and on the ground. The female lays 5 to 12 eggs, and both parents take turns incubating the eggs for around 28 to 30 days.

5. Vocalizations

Egyptian Geese are known for their loud honking calls, which they use to communicate with each other. Their calls can be heard from long distances and are often used to mark their territory or to signal danger.

6. Feeding Habits

Egyptian Geese are herbivorous and mainly feed on grasses, seeds, and other vegetation. They will also eat insects and small aquatic animals if necessary. They are diurnal and are most active in the early morning and late afternoon.

7. Social Behaviors

Egyptian Geese are social birds and often gather in flocks, especially during the non-breeding season. They have a hierarchical social structure, with dominant birds leading the flock.

8. Lifespan

Egyptian Geese can live up to 25 years in the wild. However, their lifespan is often shorter due to predation, disease, or hunting.

9. Relationship with Humans

Egyptian Geese have a long history of association with humans, dating back to ancient Egyptian times. They were considered sacred by the Egyptians and were often depicted in their artwork. Today, they are often found in parks and gardens, where they are enjoyed by people for their beauty and unique behaviors.

10. Conservation Status

Egyptian Geese are not considered endangered, with their population being stable throughout much of their range. However, they face threats such as habitat loss, hunting, and competition with introduced species in some areas.

Wrap-Up: 10 Fun Facts About the Egyptian Goose

The Egyptian Goose is a fascinating bird with a unique set of behaviors and physical characteristics. Learning more about this species can help us appreciate the diversity of life on our planet and inspire us to protect the natural world.

Fun Facts About the Egyptian Goose FAQs

What is an Egyptian Goose?

The Egyptian Goose is a species of waterfowl native to Africa. They have distinctive brown and white feathers, with a dark brown patch around their eyes.

Where do Egyptian Geese live?

Egyptian Geese are found in various habitats across Africa, including wetlands, savannas, and grasslands. They are also commonly found in urban areas and can be seen in parks and gardens.

What do Egyptian Geese eat?

Egyptian Geese are omnivorous, meaning they eat both plants and animals. Their diet typically consists of grasses, seeds, and aquatic vegetation, as well as insects, snails, and small fish.

Are Egyptian Geese endangered?

No, Egyptian Geese are not considered endangered. In fact, they are quite common and can be found in many parts of Africa, as well as in other parts of the world where they have been introduced.

Can Egyptian Geese fly?

Yes, Egyptian Geese are capable of flight and can be seen flying in formation in the wild. They are also able to fly short distances when threatened or when moving between feeding sites.

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Professor Mark Laidre holds a live adult coconut crab in its native habitat on an Indian Ocean coral atoll. (Photo courtesy of National Geographic Society)

The mighty pinch of the coconut crab

The coconut crab, or “robber crab” (Birgus latro), is the largest terrestrial arthropod in the world, with individuals weighing up to four kg (about 9 pounds).  They have a wide range:

But because of their size and the fact that they’re tasty, they’ve been largely driven extinct by humans on populated islands. Here’s how big they are:

They come in different colors, often red or blue. Here’s a beautiful blue one:

Two facts about these species. First, they’re fairly close relatives of the hermit crab, and in fact are descended from hermit crabs that occupied shells throughout their lives. But this species is sufficiently large as to have few predators besides humans, and so only the very young and small coconut crabs live in shells (sometimes bits of coconut shells). They’re also completely terrestrial, and will die if put in salt water.

You can see the hermit-crab ancestry in the reduced and curled abdomen behind the carapace:

Hermit crab without shell:

Coconut crab:

I’ve written two earlier posts on coconut crabs (here and here), including photos by reader Dennis Hansen from the Indian Ocean of Aldabra. There they invade the field station, making off with leftover food from the table, and they can also open garbage cans, as they have great climbing skills:

They’re HUGE! Second Fun Coconut Crab fact: they do indeed open coconuts, and can climb trees to get them, though they’re omnivores and coconuts are not a main part of their diet. Wikipedia gives the details (my emphasis):

The diet of coconut crabs consists primarily of fleshy fruits (particularly Ochrosia ackeringae, Arenga listeri, Pandanus elatus, P. christmatensis), nuts (coconuts Cocos nucifera, Aleurites moluccanus) and seeds (Annona reticulata), and the pith of fallen trees. However, as they are omnivores, they will consume other organic materials such as tortoise hatchlings and dead animals. They have been observed to prey upon crabs like Gecarcoidea natalis and Discoplax hirtipes, as well as scavenge on the carcasses of other coconut crabs. During a tagging experiment, one coconut crab was observed killing and eating a Polynesian Rat (Rattus exulans). Coconut crabs may be responsible for the disappearance of Amelia Earhart’s remains, consuming them after her death and hoarding her skeletal remnants in their burrows.

The coconut crab can take a coconut from the ground and cut it to a husk nut, take it with its claw, climb up a tree 10 m (33 ft) high and drop the husk nut, to access the coconut meat inside. They often descend from the trees by falling, and can survive a fall of at least 4.5 metres (15 ft) unhurt. Coconut crabs cut holes into coconuts with their strong claws and eat the contents, although it can take several days before the coconut is opened.

Thomas Hale Streets discussed the behaviour in 1877, doubting that the animal would climb trees to get at the nuts. In the 1980s, Holger Rumpff was able to confirm Streets’s report, observing and studying how they open coconuts in the wild. The animal has developed a special technique to do so: if the coconut is still covered with husk, it will use its claws to rip off strips, always starting from the side with the three germination pores, the group of three small circles found on the outside of the coconut. Once the pores are visible, the coconut crab will bang its pincers on one of them until they break. Afterwards, it will turn around and use the smaller pincers on its other legs to pull out the white flesh of the coconut. Using their strong claws, larger individuals can even break the hard coconut into smaller pieces for easier consumption.

Clearly, these animals must be strong. Indeed, they can lift up to 28 kg (62 pounds)—at least seven times their own weight.

This is all leading up to a new paper published in PLOS ONE by Shin-Ichiro Oka et al. (reference and free download below), in which the authors measured the pinching force of 29 coconut crabs. As you might expect, they pinch hard, exerting more force per gram of body weight than nearly any other animal, including terrestrial carnivores. source

Coconut crabs are the world’s largest land-dwelling crab © pattfwi via Flickr (CC BY-SA 2.0)

Coconut crabs: the bird-eating behemoths thriving on isolated tropical islands

You may be familiar with hermit crabs, the adorable and often tiny crustaceans that totter along the beach toting their bodies in seashells.

Meet their enormous relatives, coconut crabs. Their leg span is up to a metre, they have incredible grip strength and they can lift objects the weight of a 10-year-old child.

Coconut crabs (Birgus latro) might seem unusual: they’re absurdly large, land-dwelling, bird-hunting crustaceans. But on their isolated island homes, their peculiar traits work incredibly well for them.

What is a coconut crab?

To say that coconut crabs are big would be an understatement.

‘They’re a mega-crab, really,’ explains Miranda Lowe, Principal Curator of Crustacea at the Museum. ‘They range, but they can be huge – up to a metre leg span.’

They’re not quite the world’s largest crab – that would be the Japanese spider crab (Macrocheira kaempferi), which can reach a whopping 3.7 metres from claw to claw.

But the coconut crab is the largest crustacean that spends all its adult life on land, with a Guinness World Record to prove it. It’s also the biggest land-dwelling arthropod, the group of invertebrates that also includes insects, spiders and centipedes.

Coconut crabs can live up to 60 years, reaching sexual maturity at about five years old. They mate between May and September and females release their eggs into the water.

When they hatch, the larvae disperse on floating coconuts, logs or other rafts for four to six weeks. They then transform into shrimplike creatures called glaucothoe and sink to the seabed to find a suitable gastropod shell for protection. They will then begin to migrate towards the shore, spending another four weeks around the high-tide mark before they become juvenile crabs.

As adults they no longer use gastropod shells and instead rely on their tough exoskeleton to protect them from predators.

Although they spend their multiple larval stages in water, when coconut crabs eventually become adults, they can’t swim. In fact, they drown if they end up underwater for a prolonged period. This is because instead of gills, they have branchiostegal lungs that allow them to breathe air.

Coconut crabs are found across the Indo-Pacific, from islands off the coast of Africa near Zanzibar to the Gambier Islands in the Eastern Pacific Ocean. They are typically found in coastal forests with plenty of rock crevices and soil for digging burrows. On some islands, they can be found up to six kilometres from the shore.

What do coconut crabs eat?

Their name might give it away, but coconut crabs are known for cracking into green coconuts to feast on the white flesh inside.

‘Their walking legs are kind of curved and clawlike, and they have an inward grip so they can climb palm trees and other trees,’ explains Miranda.

Coconuts aren’t all they’ll munch on, however. Coconut crabs will eat fallen fruit, nuts and seeds.

Perhaps unexpectedly for crabs, they are also rather ruthless predators.

‘Most other crabs live exclusively on the water’s edge or in the ocean, and their food source is dead animals – marine worms, the flesh of other dead crabs, that sort of thing. They’re not exactly vicious hunters.’

Coconut crabs, however, are known predators of rats, others of their own species and even large migratory seabirds, such as boobies that they find nesting on their islands. They have been spotted mounting attacks in the dark of the night and grabbing unsuspecting prey that pass too close to the crabs’ burrows.

Miranda says, ‘It’s an adaptation because of their food source. On land, some of the time they have to find something else other than coconuts.’

Coconut crabs’ broad diets have even led some to suggest that the reason famed aviator Amelia Earhart was never found when she disappeared mid-flight over the Pacific Ocean was because she was devoured by coconut crabs after perishing on Nikumaroro island.

How strong is a coconut crab?

If you have ever tried to open a coconut, you’ll know it can be a bit of a challenge. Not so for a coconut crab.

Armed with two large and powerful pincers, coconut crabs can pound and rip their way through the tough exterior of a coconut with relative ease.

Miranda says, ‘People may be familiar with crab pincers if they try and pick the animals up from the front and not the back. Coconut crabs’ pincers have a serrated edge, which are commonly known as teeth because they do act as teeth on the front claws. They’re used to crack open the coconuts.’

The squeeze of a coconut crab’s pincers can be much stronger than a human’s grip. Scientists tested the force exerted by 29 wild coconut crabs, unintentionally getting themselves pinched several times  in the process, and found a maximum force of a little over 1,765 newtons. For reference, humans have a maximum bite force of between 1,100 and 1,300 newtons, based on a study using virtual models of human skulls.

The bigger the mass of the crab, the greater the pincer force. When scaled up for a fully grown, four-kilogram coconut crab, the maximum force would be around 3,300 newtons.

Coconut crabs can also lift up to about 30 kilograms, approximately the weight of a 10-year-old child. Their powerful claws and strength are essential for accessing their various food sources.

Coconut crabs and humans

There haven’t been many large-scale studies on the populations of coconut crabs. We don’t accurately know how many there are, but the International Union for Conservation of Nature lists them as a Vulnerable species.

Coconut crabs don’t have many predators, thanks to their often isolated island homes. However, one of the biggest threats they face is from humans.

Miranda explains, ‘They’re such a large crab, so obviously they’ve got lots of crab meat in them. It’s really difficult to tell islanders that you should protect the species when it’s their food source.

‘Communities rely on them for food, but also to sell. It can have a major impact on the species.’

Coconut crab populations have been depleted on inhabited islands from overharvesting, but also habitat loss. Their slow population growth rate will add up to be a problem for the species’ survival.

There are regulations to help protect coconut crabs across many of the Pacific islands they inhabit, though the specifics of these are determined by each country.

Minimum harvest sizes are used on many Pacific islands – in some locations, females carrying eggs on their underside are also specifically protected. Some governments have set quotas for the amount of crabs that can be caught, and permits may be required to export this species, although in other areas exporting coconut crabs is entirely prohibited.

Another threat to the species is the total loss of their island homes. Many populations of coconut crabs depend on low-lying island atolls. Sea level rise caused by climate change is a big threat to these types of habitats, with some at risk of being entirely lost to the ocean.

By Emily Osterloff source

Come See a Coconut crab – at the San Francisco Zoo