Breeding the Bumblebee Goby by Tom and Pat Bridges

Bee Keeping
Breeding the Bumblebee Goby
Brachygobius nunus

by Tom and Pat Bridges
First published in "The Scat" - St. Catherine's Aquarium Society, Canada. March 2001
Aquarticles

Bumblebee Gobies belong to the genus Brachygobius. Since brachy is Greek, for short, that comes to 'short goby' - so far an accurate description for these approximately 11/2 inch (40 mm) fish. The goby part has something to do with their having two dorsal fins, (or one interrupted one) and more to do with their ventral fins being fused to form a kind of natural suction cup which allows them to stick themselves to almost any surface at almost any angle.

After much eye strain both by me and my friend Paul McFarlane, trying to accurately count the rays in their anal fins, our best guess as to species is 'nunus', (supposed to have 1 spine and 7 rays). I understand that a nunus is a friendly little hole-dwelling creature in mythology and, once again, this fits our fish very well.

Male Bumblebee Goby

Female Bumblebee Goby

The 'Bumblebee' part of their common name obviously has to do with their big heads, (compared to their bodies), the four brown/black vertical stripes on a yellow/gold background and their habit of usually 'buzzing' from one surface to another as a means of moving about their tank.

The several species of Bumblebee Gobies come from Asia, where they are found in salt water swamps and stream estuaries in India, Thailand, Indonesia, Borneo and Malaysia. Although most of them can tolerate completely fresh water, they are more comfortable in a brackish environment and we are in the habit of adding at least two teaspoons of artificial sea salt mix per gallon to their tank.

They may eat a bit of dried flake food but it doesn't get them excited. Live and frozen foods are their favourites. Whiteworms are quickly gobbled up. Daphnia and brine shrimp don't last very long either. When those aren't available, frozen blood worms and shrimp seem fairly acceptable.

We bought our first dozen of these neat little creatures some years ago. The literature suggested that they were probably the easiest of the gobies to breed and we found them attractive. At first we put them in a large tank, (100 gallons), where they hopped about happily but did nothing breeding-wise. Some accounts of successful spawnings suggested a small tank, so we moved them to a 5 gallon setup with some snail shells and bricks for caves.

Over the next couple of years nothing happened except that from time to time one died. We began to wonder if, by some fluke, we didn't have both sexes. We pretty much gave up on them and there was just one left in the tank. It was four or five years old and healthy. About that time we found a tank full of tiny bumblebees in a pet store at a reasonable price and decided to start again. A dozen were purchased and placed in a ten gallon tank with an undergravel filter and a cluster of barnacle shells for caves. This group was fed on live and frozen stuff and, finally, after they had grown some, the one 'left over' was moved in with them. Some of them grew chubbier than the rest but still no spawning.

Group cleaning up whiteworms

We decided to make a concentrated effort. Larger and more frequent water changes were made, (twice a week), and more salt was added bringing it up to about a tablespoon per gallon. As much as possible they were spoiled with live food.

Late in September 2000 I noticed one morning that something strange was happening. For a few minutes I thought some other species of fish had jumped into that tank. Two or three of them were swimming about rapidly like regular fish, (not hopping), and they were an almost uniform pale yellow/gold colour. Only by looking closely could I see traces of the dark vertical stripes. I wondered if our change in treatment had made them sick.

Male in breeding dress

They were acting a bit demented. I settled down to watch and, since they were darting in and out of the caves in their barnacle, I thought, maybe not demented, maybe, finally, spawning activity.

They were indeed the males. The females were obvious. They hadn't changed colour at all. If anything their stripes seemed even darker and they were very rotund. The antics of the males appeared to be working because some of the females were definitely hanging around the cave entrances. Once in awhile one would pop inside for a moment.

Two plump females

Apparently, at least one female agreed to stay a bit longer and lay some eggs because, a few days later, a patch of eggs could be seen suspended like little sacks from the top and sides of one of the caves, and the male, (now back to normal colour), was in there on guard. He came out and looked menacing when any other fish came too close. Perhaps the eggs had been there longer than I realized because, 4 days later many little transparent slivers with, except for their eyes, just one spot visible in the middle of their bodies, were swimming around in the tank.

Baby (enlarged)

We quickly prepared a 5 gallon tank with a box and a sponge filter and partially filled it with water syphoned from the parent's tank -- along with as many of the hatchlings as I could suck into the syphon hose. A small fine-meshed net was used to catch a bunch more and the rest were left to their fate. The rearing tank was gradually topped up with fresh water at about the same salinity to avoid any shock to the babies. A rough count showed that I had captured at least 80 fry and that was plenty. Those that remained in the parents' tank lasted for 2 or 3 days and then gradually disappeared.

We fed the fry paramecium, vinegar eels and, sparingly, liquid fry food for a few days and then began adding a little newly hatched brine shrimp nauplii. When the inevitable pink bellies appeared we continued with vinegar eels and shrimp nauplii only. The tank was kept very clean with partial water changes being done every day. Growth was fairly rapid.

In a couple of weeks they began showing dark stripes and fairly soon they proved that their ventrals were fused because they began sticking to surfaces more and swimming freely less. I had never thought of duckweed as lethal but we lost several babies because they appeared to get stuck to the duckweed roots and were somehow unable to let go. I guess they starved to death. I removed all remaining bits of duckweed.

Babies with stripes

Looking more like their parents

They keep on growing

By November the babies were small, perfect replicas of their parents and we even took a bag to Brampton's auction. I guess the idea of brackish water must have scared all those cichlid types because the auctioneer had to work hard to get any bid at all.

Does this mean that Bumblebee Gobies are worthless? We don't think so. It means that, around here anyway, you won't get rich by breeding them but the satisfaction of spawning and rearing a tankful of these little charmers is a fine reward in itself.