Thanks to good weather, the May Fish-Watch trip included 3 Fish-Watch Dives with Underwater World from Durban and African Watersports in Umkomaas and 9 fish collecting dives. As usual with Fish-Watch trips, our collections and Fish-Watch Dives serve a multitude of interests. The Fish-Watch Dives not only provide the opportunity to assist divers in identifying fishes and help them to learn more about fishes and the benefits of joining the Project, but these dives also provide the opportunity for us (Grahamstonians) to get in the water to collect fishes and study the fish diversity of Aliwal Shoal.
In our first collection at Sodwana, we got a rare halfscaled jawfish, Opistognathus margaretae. This little jawfish was previously known from one specimen from Sodwana Bay, one from Kenya and two from Ponta do Ouro, Mozambique. Jawfishes live in burrows, and they have a very large mouth – even larger in the male, as he carries the fertilized eggs in his mouth for several days until they hatch. Our photograph is the first good photo of a fresh specimen.
We caught a juvenile yellowtail damselfish, Pomacentrus trichourus. Our photo documents the juvenile colour pattern, which shows a blue-ringed black ocellus in the soft dorsal fin.
On our first Fish-Watch Dive at Aliwal we did Wrasses Part 1, and I was surprised to see the cigar wrasse. Cheilio inermis. In the pre-dive briefing, I mentioned that although the cigar wrasse was shown on the underwater Worksheet that we were using for this dive, it was unlikely that we would see any on the Shoal; as this species is typically seen on seagrass beds, and there isn’t much in the way of seagrass beds on the Shoal. In fact, I saw 3 cigar wrasses on this dive; none were over seagrass, and one was swimming alongside a large blacksaddle goatfish, Parupeneus rubescens. The wrasse was probably expecting the goatfish would frighten some prey from the sandy patches on the Shoal as the goatfish roots about with its snout and barbels looking for food.
HAWKFISHES (Family Cirrhitidae): We have recently made significant improvements in our knowledge of South African hawkfishes. On this latest visit, we got an adult of the humpback hawkfish, Cirrhitichthys guichenoti at Manta Point. It looks similar to the spotted hawkfish, Cirrhitichthys oxycephalus, but it has a longer snout (snout length greater than eye diameter) and a distinctly humped back. This species was previously known from Mauritius and Madagascar, and the small juvenile that we got at Aliwal last year is the first record of the species from southern Africa. And we also collected the paletail hawkfish, Cirrhitichthys aprinus at Aliwal. This Indo-West Pacific species was reported from the Maldives in 1998, but our specimen is the first record for southern Africa. (to read our article about these fish, click here).
We collected a large specimen of the undescribed scaly-jaw koester, (Acanthistius sp 188.2 from Smiths’ Sea Fishes). This specimen lacks the characteristic dark brown oval blotch on the gill cover; but this fish is an adult male, and it seems likely that the dark blotch on the gill cover is characteristic of the smaller (female) specimens of this species. Like most serranids, the koester is probably a sequential hermaphrodite: after spawning as a female for a year or two, it changes sex and functions as a male for the rest of its life.
We got another brown banded pipefish, Halicampus zavorensis. This is the second specimen collected from Aliwal; previously known from 3 fish collected from Mozambique and Oman.
We can now add the narrow-striped
pipefish, Doryrhamphus bicarinatus, to our list of Aliwal fishes.
Previously known from Sodwana and Inhaca Island.
Dragon moray, Enchelycore pardalis, Aliwal Shoal; this is the second specimen collected in South African waters, the first specimen was found in tide pool at Scottburgh. A photo of a dragon moray from Sodwana was recently submitted by new members Stef and Fanie Kriel.
We collected and photographed a male rough-head triplefin, Norfolkia brachylepis in breeding colours and showing a russet second dorsal fin.
We collected what appears to be Fusigobius humeralis at Sodwana; a new goby for southern Africa. Previously known in the Indian Ocean from the Maldives, Red Sea and Chagos.
A pair of new dragonets, (Family Callionymidae) were collected at Aliwal Shoal. The male has a tall, colourful first dorsal fin; the female is not so spectacular. This species appears to be different from the dragonets known for southern Africa.
This trip was also useful for training two students from the Department of Ichthyology and Fisheries Science, James Stapley and Monica Mwale. James is an “old hand” on Fish-Watch trips, and he is also the Webmaster for the East Coast Fish-Watch Project. James and Monica helped with fish identification, preservation, collecting tissue samples for DNA analysis and photography. This was Monica’s first trip; she is doing her Ph.D. research on pipefish biology and taxonomy.
Another new member of the team was Steve Warren, the aquarist from Bayworld in Port Elizabeth. Steve is a Dive Supervisor, and he supervised our SCUBA dives to ensure that we dive safely and within the regulations stipulated by the Department of Labour for Scientific Diving. Steve was also successful in collecting some fishes & corals for the aquarium displays at Bayworld. We are grateful that Bayworld provided the opportunity for Steve join us.
And the last member of our May team was Tom Hooper, a colleague from Rodrigues Island. Tom is involved in studies of the marine flora and fauna of Rodrigues, and Elaine and I spent 6 weeks there in September and October of last year to do a survey of the fishes at the island. Tom is also interested in our East Coast Fish-Watch Project, as he would like to do something similar at Rodrigues to help teach the local people, as well as the tourists, to better understand and appreciate their rich fish diversity.
We also continued our collaboration with EKZN Wildlife when their staff joined us for two of our fish collecting dives at Aliwal Shoal.
Elaine Heemstra was able to complete all of the required dives for her Scientific Diver Certification except for the zero visibility dives. She was a great help with fish collections, identification, photography, and record keeping.
We are grateful to Underwater World in Durban and African Watersports in Umkomaas for organising the Fish-Watch Dives at Aliwal Shoal. Mark Addison of Blue Wilderness Dive Expeditions and Neville Ayliff of Reef-Teach assisted with their knowledge of local reefs and affordable aquatic transport for our fish survey work. Fish-Watch members Ruth and Ginger Seipp of Riverview Bed & Breakfast provided Natalian hospitality and affordable accommodation.