EOL/Google Earth Monarch Butterfly Tour Now Available

Every year eastern monarch butterflies begin a journey north from their overwintering grounds in Mexican forests. The epic migration spans generations and the better part of a continent.

EOL is pleased to announce a new Google Earth tour video showcasing the migration of monarch butterflies (Danaus plexippus) in North America, and the people that help them out along the way.

This Google Earth tour is accompanied by two companion podcasts, the first of which can be found here.

This Google Earth Tour was produced by Atlantic Public Media in cooperation with the Encyclopedia of Life Learning + Education group located at the Harvard Museum of Comparative Zoology.

Climbing Perch - Anabas testudineus (Bloch)

Anabas testudineus, a small fish from Indian waters, testudineus means “turtle like^”(1) commonly called as climbing perch .This is a fish widely distributed throughout south and south east Asia. It is a very common fish found in the river and pond waters of Machilipatnam and Eluru of Andhra Pradesh. It is a Bengali delicacy and is frequently exported to West Bengal from Eluru. Its common name in Bengali is Koi and in Telugu it is called as “Gorkalu” This fish is a column feeder and a larvicidal fish (feeds upon mosquito larvae^,(2) )and hence used to control mosquito larvae. Anabas is grayish green in color and has brown fins. It grows up to 9 inches and is a very hardy fish, due to the presence of accessory respiratory organ. (Rosette like structures found very close to the pectoral fin) and is known to survive for 8 years in captivity ⁽³⁾ basically a carnivorous fish, also known to eat rice ⁽⁴⁾

 Body is covered by cycloid scales. Lateral line sense organ is identified by the black spots as conspicuous one at the base of the caudal fin ⁽⁵⁾

 Male and female fishes are identified only during the breeding season, by the difference in their color. During the breeding season, the females show a brilliant orange color with shades of yellow on the ventral side of the abdomen and also on the pelvic fin. During spawning season the abdomen of the female is slightly bulged out^.(6)

Climbing perch can live in water low in oxygen, polluted water, and also water with rotting vegetation. In such waters, the fish rises to surface and gulps air.

Anabas can survive out of water for about 6-10hours ⁽⁷⁾

During dry seasons, the fish burrows in the mud and is in resting phase. It is interesting to see the fish travelling in troops on the ground, during early morning and at times of rain storm. This is a migratory fish, migrating from one pond to another during rainy season for spawning ⁽⁸⁾

Legend about the Climbing Perch: As this fish is frequently found on tree tops and also found hanging from trees or living in water filled slits of a palm tree ⁽⁹⁾. It was believed that the fish would travel and climbing the trees. This was observed and confirmed by Lieutenant Daldrof of the Danish East India Company in the year 1797, so people believed it to be truly climbing perch for nearly 250 years. It was in the year 1927, that this myth about this fish as climbing perch was clarified by the study of B.K Das^,(10) an Indian expert on fishes.

This fish, when travelling as troops are often caught by birds such as pond crows and kites catch and carry them off and park them on tree tops, and slits of trees. Perch can live without water for days and so were found alive on most of tree tops and hence the name as climbing perch. As the myth has been cleared, it is more appropriately now called as “Walking Perch” rather than as climbing perch. ⁽¹¹⁾

REFERENCES

http://www.aquarium-glaser.de/en/anabas-cf-macrocephalus_en_1177.html

G.Chandra, I.Bhattacharjee, S.N Chatterjee and A.Ghosh(2008); “Mosquito Control by larvivorous fish”; Indian Journal of Medical Research 127; pp-13-27

Flower, (1925) “ Contributions to our knowledge of the duration of life in vertebrate animals I. Fishes; Journal; Proc Zool Society, London 1; 247-267

Jeffery B.Graham (1997); in the book titled  “Air breathing Fishes, Evolution, diversity and adaptation” Academic Press

R.Premakumari  (1988); PhD thesis titled “ Some aspects of physiology of fish under nutritional stress” submitted to Osmania University, Hyderabad, INDIA

Shantha Vijaya raghavan,  (1981); “ Some aspects of Physiology of digestion on fish. PhD thesis ; Osmania University, Hyderabad, INDIA

Hughes ,G.M and Singh , B.N (1970) “ Respiration in an air breathing fish, the climbing perch, Anabas testudineus (Bloch) I .Oxygen uptake  and carbon dioxide release in to air and water”  J Expt Biology 53;265-280

Natarajan, G.M (1972); “ Studies on the respiration of Anabas scandens (Cuvier)”, M.Sc thesis submitted to ICAR, New Delhi, INDIA

Jesse Mitchell (1864), “On the Climbing habits of Anabas Scandens”, Annals  and Magazine of  Natural History 13; 117-119

Das,B.K (1927) “ The Bionics of certain air breathing fishes of Indian, together with an account of the development of their air breathing organs” Phil. Trans .Ser.B 216: 433; 183-219

Maurice Burton,(1984) ; Encyclopedia of  reptiles, amphibians and other cold blooded animals; BPC Publishers

Submitted by

Padmavathi Godavarthy

anjanipadmavathi@gmail.com