Memaparkan catatan dengan label wild. Papar semua catatan
Memaparkan catatan dengan label wild. Papar semua catatan

Rabu, 18 April 2018

Largest Living Bird: Greater Rhea

Greater Rhea (Rhea americana) also known as ñandú (Guaraní and Spanish). - Photo by: Rufus46


Greater Rhea (Rhea Americana) is another “largest birds that still live today” also in the group of flightless birds. Greater Rhea lives in the eastern part of Southern America native to Argentina, Bolivia, Brazil, Paraguay and Uruguay. Just like its cousin, the ostrich, greater rhea lives in open areas such as grasslands, savannah or grassy wetlands. There’s a group of this bird established itself in Germany since 2000 with growing population.

Growing so big makes it harder for greater rhea to be able to fly. The average weight for an adult bird can achieve 20–27 kg (44–60 lb), while stand at 1.5 m (4 ft 11 in) to top of its head. The size also is bigger for the male bird compared to the females. The size of males can reach up to 40 kg (88 lb), stand nearly 1.83 m (6.0 ft) tall and measure over 150 cm (59 in) long, although this is uncommon.

Greater rhea with its fluffy feathers. - Photo by: parcanimalierdauvergne.fr

Greate rhea's foot is strong for running. - Photo by: jungledragon.com 

Same as other flightless birds such as ostriches and emus, they mostly rely on their legs to run away from predators (when being threatens). Their wings are useless for flights, but will work as balancer when they are changing direction during their run. Same as any other bigger birds, greater rhea has stronger legs that can be used as a weapon instead just for running.

Even though their diet mostly consists of plants, fruits and seeds, this bird also enjoys meals of insects, lizards, birds and other small animals. It is easier for this bird to adapt itself as they don’t have any trouble to find their food. That also explained how their population grows rapidly in their new territory in German.

Greater rheas, chasing each other. - Photo by: knowsleysafariexperience.co.uk

Male greater rhea nursing its eggs during the incubation process. - Photo by: Ralph Bower

Greater rhea is a solitary bird until the mating seasons. While the males are polygynous, the females at the same time are polyandrous. Few females will lay their eggs in the same nest prepared by the male; with the total of eggs can reach up to 50 eggs or more. Other special characters of this bird are the males will incubate the eggs and also taken care of their young.

Rhea eggs were collected by human and their meat also were eaten. Instead of that, rhea’s skin also been used to produce leather products. Their population was threatened by human, until the regulations, safe this bird from totally perished.






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Khamis, 29 Mac 2018

Largest Living Bird: Kori Bustard

Kori bustard (ardeotis kori), is the largest flying birds. Photo by: Winfried Bruenken


Kori Bustard (Ardeotis kori) one of the largest living bird in the world today. It's also one of the largest flying birds that still exist. It is the member of the bustard family that consists of four species throughout the world - ranging from Africa, India, and Australia.

Being the largest flying bird, kori bustard flies a short distance and only when needed. It will spend most of its time on the ground forage occasionally in low bushes and trees. Kori bustard is omnivorous birds and will eat almost anything from insects, small reptiles and small mammals, and also seeds and fruits. Being heavy, kori bustard will try to avoid flying unless necessary.

Male kori bustard (A. k. struthiunculus) displaying in Ngorongoro Conservation Area. Photo by: David Berkowitz

Female of the nominate race near Etosha National Park, Namibia. Photo by: Hans Hillewaert

The male kori bustard is larger than female can reach up to 120 to 150 cm (3 ft 11 in to 4 ft 11 in) in height with wingspan about 230 to 275 cm (7 ft 7 in to 9 ft 0 in). Its weigh can reach up to 7 and 18 kg (15 and 40 lbs). Even though they were reports mentioned about the outsized specimens with weighing up to 23 kg (51 lb) and more.

Africa has the most diversity of the bustard species and spread throughout the continent. Among them are Denham's bustard (Neotis denhamii) and Ludwig's bustard (Neotis luwigii). While, Arabian bustard (Ardeotis arabs) has its range on the East Africa.

Same as many other birds, kori bustard has its own courtship displays to impress the females. The courtship display will followed by low-pitched booming noise with inflated neck where the male will look larger. Several males will be compete among each other. There will be fight between males with serious battle in order to win the females. One male will mates will several females in his territory – different from albatrosses and swan that will mate only with one female for long period of time.

Richard Meinertzhagen holds a shot kori bustard near Nairobi in 1915, illustrating the bird's huge size. Photo by: unknown

Kori bustard flying over the grassland. Photo by: RICHARD AND EILEEN FLACK

Kori bustard's chick, between keeper's hands. Photo by: nationalzoo.si.edu

Only female kori bustard will look over their eggs. Usually 2 eggs are laid, and seldom 1 or 3. Female built their nest within the tree shrubs, termite mount or an outcrop of rocks. Their plumage colour and behaviour make their nest is hard to be spotted.

Young chicks will grow up quickly and ready to follow their mother few hours after hatched. They fledge at 4 to 5 weeks old, but only ready to fly until 4 to 5 months. Usually one of the two young make it to adulthood. Living their mother in their second year, and ready to breed when they become fully matures around three to four years old.

Kori bustard is listed Near Threatened by IUCN (2013). They are rarely since in human populated areas. The development such as power lines can kill this bird (the powerlines in Karoo kill 22 kori bustard during 5 months period). More study should be conducted in order to help this bird from extinction.






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Khamis, 15 Mac 2018

More About Salmon


School of salmons marching to their breeding ground. Photo by: PatClayton

Salmon is one of the fish largely farmed these days. The farming technologies help more people from all around the world to enjoy eating salmon at the same time avoiding wild salmon to recover from overfishing, loss of habitats due to dam constructions deforestation and development. No one knew the exact numbers of the ideal salmon in the wild, but avoiding further damage to the wild population in important before it’s too late.

There are more interesting things about salmon that we need to know. As the salmon that grows for commercial purposes only few types that suitable for the farming industries. While there are many other salmons included in this family and some of them not even migrate to the sea as other salmon do. So what happen to them? Are all of them threaten as the common salmon (Atlantic salmon: Salmo salar and Pacific salmon: genus Oncorhynchus)?

Salmon's steak. Photo by: J.Kenji López-Alt 

Chinook salmon, the largest salmon today. Drawing of Ocean Phase Chinook (king) salmon (Oncorhynchus tshawytscha). Image by: eopugetsound.org

Salmon is the group of fish in the family Salmonidae that also includes trout, char, grayling and whitefish. But the salmon that we are going to talk about are mostly the two popular group of North Atlantic (genus Salmo) and Pacific Ocean (genus Oncorhynchus) and few more species in the same family.

The main group of salmons show in the table below with their genus, names, scientific names, maximum length, common length, maximum weight, and maximum age. These are also the salmons that use as farming salmon for commercial purposes. From their maximum age, we will know their life cycles and how long it would take for the salmon to restore their population.

Genus
Common name
Scientific name
Maximum
length
Common
length
Maximum
weight
Maximum
age
Salmo
(Atlantic salmon)
Atlantic salmon
Salmo salar Linnaeus, 1758
150 cm
120 cm
46.8 kg
13 years
Oncorhynchus
(Pacific salmon)
Chinook salmon
Oncorhynchus tshawytscha (Walbaum, 1792)
150 cm
70 cm
61.4 kg
9 years
Chum salmon
Oncorhynchus keta(Walbaum, 1792)
100 cm
58 cm
15.9 kg
7 years
Coho salmon
Oncorhynchus kisutch(Walbaum, 1792)
108 cm
71 cm
15.2 kg
5 years
Masu salmon
Oncorhynchus masou(Brevoort, 1856)
79 cm
cm
10.0 kg
3 years
Pink salmon
Oncorhynchus gorbuscha (Walbaum, 1792)
76 cm
50 cm
6.8 kg
3 years
Sockeye salmon
Oncorhynchus nerka(Walbaum, 1792)
84 cm
58 cm
7.7 kg
8 years

Other than the main species of salmons there are few more salmon that we should know;

  • Black Sea salmon (Salmo labrax) - small species of salmon with 51 cm (20 in) in length on average and can reach up to 76 cm (30 in). This species inhabits the northern Black Sea coast and inflowing river. Same as other salmon they are also anadromous, lacustrine and resident river populations. Spawn in October - January. Parrs live in rivers for 2 - 4 years, then smoltify and migrate to the sea or mature in the freshwater. They can spend for another 2 - 4 years before return to the spawning areas. Their conservation status also showing least concern.
  • Danube salmon (Hucho hucho) - also known as huchen, is a large freshwater fish. They never go to the sea as any other salmon. Huchen is endemic to the Danube basin in Europe. They also reported to be found in the Dniestr basin in the historic time and in big dam reservoirs on the mountain such as Lake Czorsztyn in Poland. Huchen is a big fish with size up to 1.5 m (4ft 11 in) and weight up to 50 kg 110 lb). The modern record for largest huchen is 34.8 kg (77 lb), caught in February 1985 in Spittal an der Drau in Austria, while older records reported weights in excess of 60 kg (130 lb). Unfortunately the conservation status for huchen already reach the level of “threatened.
  • Sabertooth salmon (Oncorhynchus rastrosus) - is an extinct species of salmon that can grow to very large sizes. They lived along the Pacific coast of North America in the late of Miocene Period, near California. The adults grew up to 2.7 m (9 ft) in length and also an anadromous like the modern salmon. They have a pair of small fangs protruding from the tip of the snout that also gave them their name. Even though so big they believe to be planktonic feeder. More about sabertooth salmon can be found here.

Black Sea salmon. Photo by: Otel,Vasile  
Danube salmon. Photo by: Hartl,Andreas
The display of saber-tooth salmon at Museum of Natural and Cultural History in Eugene. Photo by: RACHAELMCDONALD

Yes there are many other fish in the same family of Salmonidae. If you want to know more details about the sub-species in this family the best place to look for them is through fishbase. While salmon farming get better in producing good quality of salmon every year and the wild salmon population getting increases. The sub-species of salmon too should be taken care off too. With more knowledge shares among publics the awareness of conservation will be taken more seriously by each individual.



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Rabu, 7 Februari 2018

The Wonderful of Birds Migration

Canadian geese on its flight to migrate to safer breeding places - photo: M. Horath

Some birds flying thousands of miles a year migrating between two places across the continent to find suitable places to breed, feed and rising their chicks. Migration happens in so many ways from short distance, medium distance, long distance or some of the birds will stay at the same place throughout the year.

Studies of birds’ migration had been improved with the advancement of technologies available today. Even though today the studies can be conducted properly with satellites tracking devices, the birds’ populations are getting decreases as their natural stopover areas had been used for development by human. Other threats also caused by plastics pollution that killed many birds and also their main sources of foods.

With the proper studies, action can be taken in order to identify the important areas for migratory birds can be protected in order to help them to complete their journey. Most of these areas are wetlands and coastal areas that become their main feeding grounds during their journey across the globe.

Migrating waders in Roebuck Bay, Western Australia - photo: Mdk572

Birds migrate in order to make sure the availability of the food resources. While during the mating seasons they also need to make sure that the areas they select is safe to raise their young. Many migratory birds migrate in large groups, while the short range migratory birds might migrate in smaller numbers. Since these patterns of migration had been going on for long period of times, the ecosystem in both migratory areas are suitable to support their needs.

Among the long-distance migration, Arctic tern (Sterna paradisaea) known to be the longest migrator by flying from Arctic breeding grounds and the Antarctic each year. Other long-distance migrators include short-tailed shearwater (Puffinus tenuirostris), ruff (Philomachus puganx), northern wheatear (Oenanthe oenanthe), Amur falcon (Falco amurensis) and many other birds that migrates in order to find better places with plenty of foods.

Migration pattern few species of birds - by: L.Shyamal
Arctic tern migrate the longest distance - photo: Toivo Toivanen & Tiina Toppila

Some birds might migrating in smaller distance - photo: Ken Thomas

Even though harnessing plenty of food resources in the areas where they stays, migratory birds also will enrich it with their faeces to increase the blooming of algae and fertilized the areas to make it suitable for other life to grows by the time they return the following year. This is why the migrating process keep on continuing for long period of times – until we change the environment.

The same thing with medium-distance and short-distance migrators. They also balancing the amount of their food resources. Spreading the seeds, improve the soils, increase the drainage (when they scratching the ground to find food), controlling pest and many other things that birds do.


Mass flocking of bird will enrich the areas - photo: Times of India

Equipped with wings, birds are the animals that can travels further in order to shapes the world compared with fish that can only travel to areas covered with water (and either they are salt-water fish or fresh-water fish). For millions of years birds the only travellers that can go from end to end of the world in order to balance their ecosystem.


Birds’ migrations are one of the best things to observe in nature. From there, there are many things interconnected together with other lives wherever they stop. As the time goes by, everything will keep on flourishing until they come again the following year.


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