Morphological and habitat characteristics of settling and newly settled Roughscale Sole Clidoderma asperrimum collected in the coastal waters of northeastern Japan

AbstractWe evaluated the effects of turbidity on school formation in ayu (Plecoglossus altivelis) [24.5 ± 2.2 mm standard length (Ls)], Japanese anchovy (Engraulis japonicus) (29.1 ± 3.1 mm Ls) larvae, which often live in turbid coastal waters, and yellowtail (Seriola quinqueradiata) juveniles (37.1 ± 2.5 mm Ls), which live in clear offshore waters. Fish were introduced into experimental tanks at one of five turbidity levels obtained by dissolving 0, 5, 20, 50, or 300 mg l−1 of kaolin in seawater. Their behaviour was video recorded, and the nearest neighbour distance (DNN) and separation angle (AS) were compared among turbidity levels. Mean DNN of ayu was significantly smaller at 20 and 50 mg l−1 than any other level of turbidity, as was AS at 20 mg l−1 compared with 0 mg l−1. Mean AS of anchovy was smaller at 50 mg l−1 of turbidity than any others. In contrast, mean DNN of yellowtail was larger at 300 mg l−1 than any others. These results suggest that moderate turbidities enhance schooling behaviour in ayu and Japanese anchovy larvae, whereas turbidity has an inhibitive effect on schooling of yellowtail juveniles, corresponding well to the habitat characteristics of each species.

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Behavioral and Biophysical Studies of Dugong (Dugong dugon) Habitat in Waters Mali Beach, Kabola District, Indonesia.

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/934/1/012077 ◽

2021 ◽

Vol 934 (1) ◽

pp. 012077

Author(s):

P E Plaimo ◽

I L Wabang ◽

A Hendrizal

Keyword(s):

Coastal Waters ◽

Habitat Characteristics ◽

Abiotic Conditions ◽

Pectoral Fins ◽

Observation Methods ◽

Daily Behavior ◽

Biophysical Studies ◽

Close Distance ◽

Habitat Environment ◽

Activity Areas

Abstract Dugongs are generally shy animals, so observing their existence is very limited to hundreds of meters. In contrast to the behavior of Dugong who lives in the coastal waters of Mali, Kabola Regency, Indonesia. Its uniqueness can interact with humans at a very close distance and can even be on the back. It is, therefore, necessary to explore other behavioral patterns and habits and biophysical habitats of Dugongs as information to maintain their survival. This research aims to find out the behavior and biophysics of dugong habitat in the coastal waters of Mali, Kabola Subdistrict, Indonesia. The study uses direct observation methods in the form of observing the characteristics and biophysical conditions of dugong habitats including (1) determining dugong activity areas using GPS coordinates; (2) observe habitat characteristics and biophysical conditions by observing biotic and abiotic conditions, and (3) measuring physicochemical parameters, namely temperature, salinity, and pH. Next, to observe the daily behavior of dugongs when interacting with their habitat environment in the form of time: breathing, going around the boat, swimming at the bottom, swimming on the surface, swimming in the water column, resting at the bottom, eating and exposing the back. In the observations, dugongs swimming around the ship immediately responded and then approached and rubbed his body to the leg then through the pectoral fins that tried to hug to get a leg on the model being tested. Then turn under the boat and remove the penis. In general, the biophysical conditions of sandy and dense habitats are overgrown with seagrass.

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Distribution and habitat characteristics of three sympatric cetacean species in the coastal waters of Matang, Perak, Peninsular Malaysia

Aquatic Conservation Marine and Freshwater Ecosystems ◽

10.1002/aqc.3121 ◽

2019 ◽

Vol 29 (10) ◽

pp. 1681-1696 ◽

Cited By ~ 2

Author(s):

Sui Hyang Kuit ◽

Louisa Shobhini Ponnampalam ◽

Jol Ern Ng ◽

Ving Ching Chong ◽

Amy Yee‐Hui Then

Keyword(s):

Coastal Waters ◽

Peninsular Malaysia ◽

Habitat Characteristics ◽

Cetacean Species

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Feeding Habits of the Japanese Flounder Paralichthys olivaceus in Pacific Coastal Waters of Tohoku District, Northeastern Japan.

NIPPON SUISAN GAKKAISHI ◽

10.2331/suisan.64.249 ◽

1998 ◽

Vol 64 (2) ◽

pp. 249-258 ◽

Cited By ~ 28

Author(s):

Hideaki Yamada ◽

Keiichi Sato ◽

Sachio Nagahora ◽

Atsushi Kumagai ◽

Yoh Yamashita

Keyword(s):

Coastal Waters ◽

Feeding Habits ◽

Paralichthys Olivaceus ◽

Japanese Flounder ◽

Northeastern Japan

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Molecular identification and larval morphology of spionid polychaetes (Annelida, Spionidae) from northeastern Japan

ZooKeys ◽

10.3897/zookeys.1015.54387 ◽

2021 ◽

Vol 1015 ◽

pp. 1-86

Author(s):

Hirokazu Abe ◽

Waka Sato‐Okoshi

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Coastal Waters ◽

Body Shape ◽

Rrna Gene ◽

Larval Morphology ◽

16S Rrna Gene Sequences ◽

Northeastern Japan ◽

The Family ◽

Species Specific

Planktonic larvae of spionid polychaetes are among the most common and abundant group in coastal meroplankton worldwide. The present study reports the morphology of spionid larvae collected mainly from coastal waters of northeastern Japan that were identified by the comparison of adult and larval 18S and 16S rRNA gene sequences. The molecular analysis effectively discriminated the species. Adult sequences of 48 species from 14 genera (Aonides Claparède, 1864; Boccardia Carazzi, 1893; Boccardiella Blake & Kudenov, 1978; Dipolydora Verrill, 1881; Laonice Malmgren, 1867; Malacoceros Quatrefages, 1843; Paraprionospio Caullery, 1914; Polydora Bosc, 1802; Prionospio Malmgren, 1867; Pseudopolydora Czerniavsky, 1881; Rhynchospio Hartman, 1936; Scolelepis Blainville, 1828; Spio Fabricius, 1785; Spiophanes Grube, 1860) and larval sequences of 41 species from 14 genera (Aonides; Boccardia; Boccardiella; Dipolydora; Laonice; Paraprionospio; Poecilochaetus Claparède in Ehlers, 1875; Polydora; Prionospio; Pseudopolydora; Rhynchospio; Scolelepis; Spio; Spiophanes) of spionid polychaetes were obtained; sequences of 27 of these species matched between adults and larvae. Morphology of the larvae was generally species‐specific, and larvae from the same genus mostly shared morphological features, with some exceptions. Color and number of eyes, overall body shape, and type and arrangement of pigmentation are the most obvious differences between genera or species. The morphological information on spionid larvae provided in this study contributes to species or genus level larval identification of this taxon in the studied area. Identification keys to genera and species of planktonic spionid larvae in northeastern Japan are provided. The preliminary results of the molecular phylogeny of the family Spionidae using 18S and 16S rRNA gene regions are also provided.

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