Giant Otter *800*
|[Note Guidelines] Photographer's Note|
|My 800th posting. |
Taken from the same place as where I photographed the caiman with the fish in its mouth. After I had driven away a few caimans, I sat down on a small sandy beach on the banks along the river, surrounded by dozens of caimans, a family of eating giant otters and many beautiful birds.
The giant otter (Pteronura brasiliensis) is a South American carnivorous mammal. It is the longest member of the Mustelidae, or weasel family, a globally successful group of predators, reaching up to 1.7 m. Atypical of mustelids, the giant otter is a social species, with family groups typically supporting three to eight members. The groups are centered on a dominant breeding pair and are extremely cohesive and cooperative. Although generally peaceful, the species is territorial, and aggression has been observed between groups. The giant otter is diurnal, being active exclusively during daylight hours. It is the noisiest otter species, and distinct vocalizations have been documented that indicate alarm, aggressiveness, and reassurance.
The giant otter ranges across north-central South America; it lives mostly in and along the Amazon River and in the Pantanal.
The giant otter is clearly distinguished from other otters by morphological and behavioral characteristics. It has the greatest body length of any species in the mustelid family, although the sea otter may be heavier. Males are between 1.5 and 1.7 m in length from head to tail and females between 1 and 1.5 m. The animal's well-muscled tail can add a further 70 cm to the total body length. Early reports of skins and living animals suggested exceptionally large males of up to 2.4 m; intensive hunting likely reduced the occurrence of such massive specimens. Weights are between 26 and 32 kg for males and 22 and 26 kg for females. The giant otter has the shortest fur of all otter species; it is typically chocolate brown, but may be reddish or fawn, and appears nearly black when wet. The fur is extremely dense, so much so that water cannot penetrate to the skin. Guard hairs trap water and keep the inner fur dry; the guard hairs are approximately 8 millimeters in length, about twice as long as the fur of the inner coat. Its velvety feel makes the animal highly sought after by fur traders and has contributed to its decline. Unique markings of white or cream fur color the throat and under the chin, allow individuals to be identified from birth. Giant otters use these marks to recognize one another, and upon meeting other otters, they engage in a behavior known as "periscoping", displaying their throats and upper chests to each other.
Giant otter muzzles are short and sloping and give the head a ball-shaped appearance. The ears are small and rounded. The nose (or rhinarium) is completely covered in fur, with only the two slit-like nostrils visible. The giant otter's highly sensitive whiskers (vibrissae) allow the animal to track changes in water pressure and currents, which aids in detecting prey. The legs are short and stubby and end in large webbed feet tipped with sharp claws. Well suited for an aquatic life, it can close its ears and nose while underwater.
Field observations show the animal primarily hunts by sight; above water, it is able to recognize observers at great distances. The fact that it is exclusively active during the day further suggests its eyesight should be strong, to aid in hunting and predator avoidance. In other otter species, vision is generally normal or slightly myopic, both on land and in water. The giant otter's hearing is acute and its sense of smell excellent.
The giant otter is an especially noisy animal, with a complex repertoire of vocalizations. All otters produce vocalizations, but by frequency and volume, the giant otter may be the most vocal. Duplaix identified 9 distinct sounds, with further subdivisions possible, depending on context. Quick HAH! barks or explosive snorts suggest immediate interest and possible danger. A wavering scream may be used in bluff charges against intruders, while a low growl is used for aggressive warning. Hums and coos are more reassuring within the group. Whistles may be used as advance warning of nonhostile intent between groups, although evidence is limited. Newborn pups squeak to elicit attention, while older young whine and wail when they begin to participate in group activities.
The giant otter is a highly social animal and lives in extended family groups. Group sizes are anywhere from two to 20 members, but likely average between three and eight. (Larger figures may reflect two or three family groups temporarily feeding together.) The groups are strongly cohesive: the otters sleep, play, travel, and feed together.
Group members share roles, structured around the dominant breeding pair. The species is territorial, with groups marking their ranges with latrines, gland secretions, and vocalizations. At least one case of a change in alpha relationship has been reported, with a new male taking over the role; the mechanics of the transition were not determined. Duplaix suggests a division between "residents", who are established within groups and territories, and nomadic and solitary "transients"; the categories do not seem rigid, and both may be a normal part of the giant otter life cycle. One tentative theory for the development of sociality in mustelids is that locally abundant, but unpredictably dispersed, prey causes groups to form.
Its distribution has been greatly reduced and is now discontinuous. Decades of poaching for its velvety pelt, peaking in the 1950s and 1960s, considerably diminished population numbers. The species was listed as endangered in 1999 and wild population estimates are typically below 5,000. It is one of the most endangered mammal species in the neotropics. Habitat degradation and loss is the greatest current threat.
The giant otter shows a variety of adaptations suitable to an amphibious lifestyle, including exceptionally dense fur, a wing-like tail, and webbed feet. The species prefers freshwater rivers and streams, which are usually seasonally flooded, and may also take to freshwater lakes and springs. It constructs extensive campsites close to feeding areas, clearing large amounts of vegetation. The giant otter largely subsists on a diet of fish, particularly characins and catfish, and may also eat crabs. It has no serious natural predators other than humans, although it must compete with other species, including the neotropical otter and caiman species, for food resources.
maaciejka, drchoneydew, Hotelcalifornia, marius-secan, robertcolino, KOMSIS, kinglove, CeltickRanger, nagraj, jcoowanitwong, Ishi, Hormon_Manyer has marked this note useful
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congratulations for Your 800th photo.
This one is amazing. Great composition. Perfect point of view.
Thanks for sharing,
- [2013-12-26 7:17]
That is the kind of picture we all would like to take one day
WOW can see the tonsils on this guy! Great capture! Know the excitement you must have felt;found three young ones scurrying one day and gosh were they FAST. AND this being your 800th post WOW a mouthful indeed ;) Well done my friend, your sandy beach spot is a keeper!
Congratulation for you journey and touch the 800th milestone.
Beautiful presentation of this Otter.Nice clear view of its lunch time.Splendid sharpness with nice light.
Thanks for sharing,
Regards and have a nice time,
Ciao Peter, congtratulations for your 800th post on YN, thanks for all your beautiful photo and for your friendship, great portrait of lovely otter, finre details, excellent clarity, wonderful colors and splendid light, very well done, my friend, ciao Silvio
Congratulation for your 800th post. It is great task and it takes very much time to shoot those superb images you post along this years....Thanks for your great contribution and helping this photo community which is TN.
Once again you post a rare image.....taken from a very good angle and POV. Exceptional details and perfect focus. Outstanding colors.
Thanks for sharing!
Congratulations for Your 800th photo. Great capture. Great light and sharpness.
Marvellous information note.
Thanks a lot.
- [2013-12-26 9:47]
Congratulation with your 800th post on TN ..
Lovely capture with a very good focus, sharpness, colors, details and composition.
光線亮麗 構圖美麗 背景深遂
What a stunning picture.
Congratulation for your 800th posting.
- [2013-12-26 19:27]
Hello Peter, Congratulations on your 800th. post!!
A wonderful close-up shot of this cute little otter. Looks like it was a bit preoccupied at the moment and doesn't mind you taking it's picture.
This is one animal that is very elusive here in Ohio. We have River Otters living in the state, but you only see them on very rare occasions.
Congratulations for your 800th posting on TN,
(I read your notes) and your POV it is also
giving an impression you was with the otter
in the water, a great POV at the level of the
animal's head on action and the glance on you, TFS
Hello Peter! Congratulations for your 800 beautiful and interesting photos in TN!
Amazing scene and GREAT photo! The timing, the composition, the colours and the sharpness are excellent!
- [2013-12-26 21:02]
Congrats! 800th post, awesome achievement...fine image of this giant otter feasting on a fish...good viewpoint and composition. tfs.
Hi Peter, Congratulations for your 800th posting on TN. This is a perfect picture for the occasion. Perfect timing to get this natural pose. Very well done. JC
- [2013-12-26 23:11]
Congrats on your 800th, Peter! We all look forward to many more!
You keep sharing with us most interesting and technically superb pix.
Thanks and best regards,
Lovely capture of the giant otter...well framed with fine details.
ur 800th pic is really giant...
- [2013-12-27 2:25]
Hi Peter,nothing better to celebrate your 800th post!! A spectacular capture of this otter,looks like a man praying in the water,great timing and great quality despite the distance.Have a nice day and thanks,Luciano
Gefeliciteerd met deze 800th foto op TN en altijd weer met een bijzondere zoals deze otter
super goed van scherpte en mooie natuurlijke kleuren
bedankt weer gr lou
- [2013-12-28 1:42]
Fantastic shot,amazing colors,good composition and sharpness details. Perfect the eye's contact.
Have a good weekend
- [2013-12-28 8:21]
Hola Peter; el solo hecho de ver esta especie y tomarle fotos es mas que suficiente, una belleza de especie bien lograda en un momento especial de su rutina diaraia, felicitaciones y feliz ańo nuevo...
Congratulations for your 800th photo and wish you a happy and prosperous new year. After clicking on your post I find myself reading at least the 3rd article about this rare mammal, although, shame I know, I've never heard of it before. Thank you very much not only for showing the species, but for educating us with your valuable contribution on TN.
Kind regards, László
Great shot! Love your story!