It has been a long time coming, but just as we see aquaculturists banging hard on the door, demanding to be let in on the secrets of captive-bred Tangs, so too we see the captive-breeding barrier being approached from every angle by breeders working with Chaetodontids. While researchers are making great strides with Surgeonfish, truth be told, we are even closer to the first captive bred Butterflyfish. I’m about to tell you exactly how close, and why.
The first captive spawning of Butterflyfish
Butterflyfish breeding perhaps goes back as early as 1980, when K. Suzuki documented the first captive spawning and rearing attempts of Chaetodon nippon in Japan. These spawnings occured in a large community aquarium, approximately 4 feet in depth, with courtship and spawning occurring during the dusk phase (typical timing for many reef fishes). According to Dr. Ronald E. Thresher’s book, Reproduction in Reef Fishes, Suzuki et al. attempted to rear the larvae of C. nippon with rotifers (Brachionus plicatilis), larval oysters (Crassostrea gigas), and larval sea urchins (Temnopleurus reevesi).
Groundbreaking Butterflyfish Breeding Research at Rising Tide / University of Florida’s Tropical Aquaculture Laboratory
Flash-forward almost 32 years (yes, longer than some of our readers have been alive) and we arrive at the groundbreaking work of Dr. Matthew L. Wittenrich, Eric Cassiano, and the rest of the Rising Tide Team at the University of Florida’s Tropical Aquaculture Lab. It was November, 2011, when Wittenrich published the jaw dropping Rising Tide update, “Schooling Bannerfish…So Close!”. Just how close? Well, they made it to 41 days post hatch with captive-spawned Heniochus diphreutes. This accomplishment is even more shocking, considering that the eggs they used were spawned miles to the north at the Columbus Zoo and Aquarium in Ohio!
Nothing else came out of Rising Tide regarding Butterflyfish until February 2013, when Jon-Michael Degidio (JMD) came on board to start work on Rising Tide’s Milletseed Butterflyfish (Chaetodon milliaris) breeding project. In summer, 2013, JMD was waist deep investigating Butterflyfish broodstock and conditioning, publishing an update on his progress with the Milletseed butterflyfish. Meanwhile, come October 2013, Dr. Wittenrich unofficially left the Butterflyfish breeding research behind when he moved back to Florida’s east coast, departing from U of F’s TAL.
Which brings us to 2014. On March 3rd, JMD published a weighty update on TAL’s progress with C. milliaris; Milletseed Butterflyfish Update: Good News / Bad News. The short of it – just over a year after this project has started, JMD is now documenting twice-a-week spawns from his broodstock, and has reared C. milliaris to 44 days post hatch. These rearing runs have been accomplished with copepods as the food source for larvae, and several rearing bottlenecks have been identified.
To recap – the efforts of the Rising Tide Team at University of Florida’s Tropical Aquaculture Laboratory have now seen larval butterflyfish, reared from eggs spawned in captivity, into the 40+ day range. In both cases, the sentiments are the same…we’re close, it’s only a matter of time….
The Hawaii Larval Fish Project – Frank Baensch’s Rearing Research and a Game Changer
I’ve had to sit on this one for a little while as the story was being prepared for CORAL Magazine and “oh my God” would not overstate the poker hand that Frank Baensch just threw down on the table. In the March/April 2014 Issue of CORAL, we included a revoluntionary article by Baensch simply titled, “The Hawaii Larval Fish Project” (HLFP). To vastly oversimplify for the sake of brevity, Baensch has moved on from his captive-breeding Angelfish days to take a different approach to marine aquaculture research. With the HLFP, Baensch has eliminated what he sees as a resource waster and time suck…he’s not keeping any broodstock. Instead, all of Baensch’s research is now being conducted with wild-harvested fish eggs.
This came to me as a bit of a shock at first. I remembered when news broke of Wen-Ping Su’s Bali Aquarich captive-bred Pinnatus Batfish and I asked him, point blank, if these were actually “tank raised”…if he had gone out into the ocean to collect the eggs as had been speculated by some. The response made a lot of sense at the time, and I could sum it up as “how the heck would I go out to the wild and find the eggs of this specific species of fish…what are the odds?!”. Yes, needle in a haystack is an understatement.
That said, Baensch didn’t see wild-collection of eggs as an impossibility, and instead, he spent substantial amounts of time and effort to develop his protocols…the “how” and “where” and “when” of finding freshly-spawned reef fish gametes in the ocean. To be fair, Baensch isn’t going so granular as to be able to say “I’m collecting only the eggs of species X”; generally speaking he’s getting a mix. This technique has already produced some stunning results, perhaps the most noteworthy you’ve read about here was the surprise rearing of the Yellowfin Anthias, Odontanthias fuscipinnis.
There is only one small technicality that I have to bring up. In every respect, Baensch is blowing the doors of the competition and rearing all sorts of easy and difficult and new species. The unfortunate side note is this – being wild-collected eggs, these juvenile fish fail to meet the official definition of “captive-bred”; they are “tank-raised” taken to the ultimate extreme. So for all of Baensch’s hard work and laudable breakthroughs, we don’t get to add new species to our captive-bred lists. It’s a technicality I wish we could simply disregard sometimes, particularly since we presume that if Frank were to be presented with the captive-spawned eggs of O. fuscipinnis, he’d probably be able to rear the species again using the same techniques he did before.
From Wild Egg to Juvenile Butterflyfish
And finally I get to break out the part of the story that “blows it all up” for me; Baensch has succeeded in rearing the Schooling Bannerfish, Heniochus diphreutes, from wild collected egg to a post-settlement juvenile; by my calculations it is probably 190+ days old now. I’ve convinced everyone to let me post an excerpt of this Butterflyfish larval rearing story from Baensch’s article in CORAL Magazine, just so I could share this monumental achievement with as wide an audience as possible. Baensch has succeeded in doing something no one else has ever done before – he has reared a Butterflyfish from egg to marketable juvenile fish in captivity.
Shoot, there’s that technicality I was mentioning; this is a tank-raised Schooling Bannerfish. What Baensch didn’t have to do was the work of collecting broodstock, conditioning them, and getting them to spawn. As Baensch relays it in his article, part of the reasoning behind using wild-spawned eggs stems from a belief that they represent the absolute pinnacle of quality and fitness; you eliminate the possibility that the eggs you get from captive-spawnings are somehow weak or inferior. It makes perfect sense to attack the rearing research in this way – eliminate one big source of potential setbacks.
They’ve Run the Race from Both Ends
So here’s how Chaetodontid captive-breeding and larviculture shapes up. On the one hand we have Rising Tide, running the race from the traditional starting point using captive-spawned eggs. Not only have they gotten to 44 days with Chaetodon milliaris, but 41 days with none other than the Schooling Bannerfish, Heniochus diphreutes.
Then, coming from the other direction, you have Frank Baensch and the Hawaii Larval Fish Project completing the race with the very same species, the Schooling Bannerfish, H. diphreutes. If you ignore a linear, chronological progression, it’s fair to say that Baensch started and the other end of of the race and worked backwards. He’s covered 95% of the same race course that Rising Tide has. While the team at Rising Tide knows what the starting line looks like, and all the prep that goes into running this race, they have yet to successfully cross the finish line. Meanwhile, Baensch has crossed the finish line and knows how to get there…he just never bothered to start the race at the absolute beginning!
Heniochus diphretues, as a species, has seen every part of it’s live cycle created and/or maintained in captivity, just not all by the same person.
Can’t say that about Tangs!
If you’re still trying to wrap your head around this, I recently put this graphic together to illustrate the current state of accomplishments with breeding and rearing Heniochus diphreutes.
So How Do We Get a Captive-Bred Butterflyfish Before The End of 2014?
The answer is incredibly simple; Baensch and the team at Rising Tide need to collaborate (and I want to be a fly on the wall). There is a MASSIVE overlap between their independent successes. From an outsider viewpoint, every component that makes an officially “captive-bred” marine Butterflyfish has been accomplished. They’ve been successfully spawned in captivity, they’ve produce viable gametes in captivity as well. They’ve been reared extensively, but not completely, from those gametes. Meanwhile they’ve also been reared all the way through to settlement and beyond from the wild-collected egg, in captivity.
All that is left here is for one person to actually run the race from start to finish. Each party overlaps by my rhetorical 95%, it’s just neither has done 100% yet. It is simply a matter of time, and I am confident that we’ll see this race done before the year is up. Dare I say before even July?! Dare I say the first captive-bred Butterflyfish species winds up being Chaetodon milliaris?