June 2000
ハエの幼虫を餌として使うことのススメ
"FROG TIPS" are methods or ideas that I use that I believe are helpful in frog keeping. Some were thought up by me and some are from friends. Some are simple ideas and are probably already in use by other people, but all tips are ones that I doubt you will find in published books on frog keeping.
KEEPING TINCS SATISFIED ON DROSOPHILA ALONE: It takes a lot of Drosophila to keep the larger dendrobatids like tinctorius and azureus satisified. One alternative is to feed them crickets, but crickets are expensive to buy in sufficient quantity for everyday use and breeding them can mean that your home will be overrun by crickets (in addition to the Drosophila already there). Because I don't breed crickets what I do to keep my larger frogs fat is to feed them Drosophila larvae in addition to adults. Whereas the protein content of Drosphila does not differ much between fully grown larvae and adults, the lipid content falls dramatically (more than half) during the pupal stages (Church and Robertson 1966). Furthermore the dry weight of a larva is 1.25 times that of an adult. In short, larvae have more nutrition than adults. Or at least adults that are newly eclosed (hatched) and not gut loaded.
In my experience, my tincs, azus, leucs and auratus will feed quite readily on larvae. I have not tried giving them to the smaller frogs with the exception of WC reticulatus and they ate them. Even if some of the larvae are not eaten they will metamorphose and be consumed when they emerge as flies.
What is even better than D. melanogaster larvae is D.hydei larvae because they are much larger than the former, and they tend stay bunched together in one spot in the culture medium, making it very easy to collect them.
By feeding your frogs larvae, you will be able to cut back on the amount insects you culture to keep your frogs happy or get those frogs that were on the slim side a little plumper and ready for breeding!
June 2000
The tadpole food I use now is "Sera micron". It is a powder form tropical fish food manufactured by the German company. "Sera". The main reasons I use it is because;
I now keep my auratus and vent tads in 20 cm of water and they swim and stay at the surface to eat it while it floats. This response is seen immediately after feeding so they seem to be able to smell it well. I guess that this surface-skimming feeding behavior is one of their natural modes of feeding. In addition to Sera micron I occassionaly feed them frozen midge larvae ("blood worms", chironomous). In case you can't get sera micron, I think it is Ok to feed your tadpoles spirulina obtained at a health-food store or flake foods like "Tetramin".
現在、オタマの餌はセラ＝ミクロンというドイツのセラ社の熱帯魚用の粉末餌を使っています。小売値は小さな容器で500円以下ですが、あまり流通しておらず、注文しなければいけないかもしれません。国内在庫はあるはずです。
この餌を使い始めた理由はアメリカの飼育者の間でとても評判がいいからです。アメリカでもあまり売られておらず、みなさん入手に苦労しているようです。この餌の主原料がスピルリナと呼ばれる単細胞の藻類で、クロレラみたいなものを想像すればいいと思います。確か、同じように塩水湖で殖えるのだと思いました。餌としての利点は高タンパクでありながら、腐敗しにくく、水質の悪化が少ないことです。スピルリナ自体は健康食品としても売られており、純粋なものを餌にした方がよいという意見もあります。セラ＝ミクロンは魚の肝臓粉末やミジンコ、ケンミジンコも含んでおり、水のよごれがスピルリナ単独より早いようです。でも、テトラミンなどよりは格段によく、食べ残しで神経を使うことがありません。
セラ＝ミクロンが一般のフレークフードより優れている点がもう一つあり、それは細かい粉末なので孵化後間もない小型種のオタマも簡単に食べられることです。普通の深い水槽に入ったオタマに与えると、セラ＝ミクロンは水面で広がり、最初は沈みませんが、臭いが強いせいか、オタマは水面まであがり、口を水面に出しながら泳ぎ続け、上手く食べます。こういう行動を観察すると、自然界でもそういう食べ方をする状況があるのだと想像したくなり、そういう発見があるのもヤドクを飼育する面白さの一つです。
June 2000
Kume-san has succeeded in breeding D.lamasi. The following are pictures of the first froglet to morph out and a new clutch of eggs. Note that the eggs are a grayish color like reticulatus eggs that is not as light as imitator eggs and not as dark as ventrimaculatus eggs. However it is not clear at this point whether these eggs are viable or not and the color of "bad" eggs often differ from "good" ones. The crescent shape of this clutch is interesting.
KさんがD.lamasiの繁殖に成功しました。仔カエルは親と同じ鮮やかな色彩と模様を持っています。卵はventriなどの黒い卵と違い、淡い灰色ですが、imitatorほど白くはありません。reticulatusもこんな色です。
The froglet has the bright colors and pattern of the adults.
Froglet with tail part gone.
Tail is completely absorbed.
長崎県のH氏のところでボアコンが出産しました。持ち込み腹ではなく、ちゃんと交配させているのです。アマチュアでは国内初、もしくはそれに近い快挙ではないでしょうか？沢山の個体が飼育されていながら繁殖していないことを考えると如何に難しいのか想像できると思います。当人は何も特別なことをしていないと言ってますが、基本的な飼育技術のレベルがそれだけ高いのだと思います。
しかし羊膜なんかが生々しく写っていて、いかにも「出産」という感じですね！
卵生のヘビにない迫力です！
The upper two photos are new tinc morphs taken by a breeder here in Japan. The lower two are photos from an exporter in Holland. The frogs seem to be identical morphs from Surinam. The suprising thing is that morphs that are new in Europe are now being shipped directly to Japan at the same time. This is a big step forward for hobbists here because, previously we had to get all of our new frogs from Germany or Holland. The blue and yellow morph is called "Patricia" and the yellow and black morph "Alanis". The story is that they were named after the daughters of the exporter of these frogs in Suriname. Judging from the frogs, the daughters most be quite attractive.
写真はスルナムからの新しいタイプのtinctoriusです。どれもなかなか魅力的です。しかし、上の２枚は有名ブリーダーのT氏が国内で撮影したものです。下の2枚はオランダの輸出業者が新種紹介で送って来たものです。驚いたことに新しいタイプのワイルド個体がヨーロッパと同時に日本に入荷するようになったのです。これは私達に取って大きな進歩です。ただ、この場合はある輸入業者がスリナム便を得意としていることも大きいかもしれません。是非、他の南米諸国も市場開拓していただきたいです。
ちなみのオランダの業者さんはシトロネラを発見した人です。
tincの名前ですが、黄色+青が"Patricia" 、黒+黄色が" Alanis"だそうです。採集地の名前ではなく、スリナムから輸出している業者の娘たちの名前だそうです。ということはその子たちが美人なのかな？
スイスに住んでいるDieterが開発したMisterです。彼が言うこのシステムの特徴は以下の通りです。
Besides feeding, the terraria are still a problem in keeping these frogs. The center problem being to maintain the right humidity. Starting from an industrial solution, I therefore developped a water atomizer with the following features: very small noiseless droplets of a size of 10-15 micrometers, therefore no fog produces negative ions the amount of atomized water can be regulated between 1 and 800 cubic centimeters per hour ( 1000 cubic centimetes equal 0,22 gallon). I would like to give you an impression of this device by the two attached pictures. On the first one the ultrasonic atomizer is pictured naked to demonstrate its dimensions and on the other one a frog is enjoying the shower of negative ions. I believe that this water atomizer together with a proper ventilation could improve the keeping of frogs a lot. Unfortunately, in Europe, there is a strong anti-technical feeling which makes it difficult to bring such a technology to market.
写真のカエルがhistrionicusの変ったモルフであるところが憎いですね。
ワシントンDC在住のJordanとShihoさんからの写真です。センスの良さが光ってます。
A friend in Germany has sent me pictures of his D. histrionicus and E. silverstoni.
ドイツの知人が送ってくれた写真。
ショウジョウバエの飼育で役立つデータ
Here is some data on Drosophila development from the book, "DROSOPHILA, A Labratory Handbook" by Michael Ashburner. This may help solve some of the Problems you have with fly cultures!
温度と成長期間の関係
Total period of development of wildtype stock grown under optimal conditions. (from Ashburner and Thompson 1978)
温度と致死率の関係
Rough values read from graph by David and Clavel (1966).
温度と雌の体重の関係
Rough values read from graph by Economos and Lints (1987).
Conclusion: development is fastest at tempertures around 28 degrees centingrade, but there is a slight rise in mortality and a loss in average body weight. At higher temperatures development takes considerably longer, and there is a significant rise in mortality.
Additionaly, Males kept at temperatures over 29 degrees centigrade will have fertility problems (Nothrop 1920). However these males will regain fertility after 4-5 days at 25 degrees C, and fertile males will lose fertility after 8 days or so at 30 degrees C (David et al 1971). Females are still fertile at 32 degrees C ( David and Clavel 1966). All of these results may explain some of the problems people have with Drosophila cultures during the summer months .
June 2000
カスリショウキョプバエの飼育のコツ
"FROG TIPS" are methods or ideas that I use that I believe are helpful in frog keeping. Some were thought up by me and some are from friends. Some are simple ideas and are probably already in use by other people, but all tips are ones that I doubt you will find in published books on frog keeping.
BREEDING DROSOPHILA HYDEI: Non-flying Drosophila hydei are great as frogfood. Both the adults and larvae are much larger than D. melanogaster and I have the impression that you get much more in total weight of flies from the same amount of culture medium (fly food), possibly because the larvae are larger and can eat their way further into the medium without suffucating. This is because drosophila breath out of their rear ends and have to have their tails sticking out in the air when the food is liquidy.
The short comings of hydei are that they are sometimes hard to get, their cultures for some reason stink even more than melanogaster, and they seem very sensitive to mite infestions. An additional difference is that they tend to climb to the very top of plants in the vivaria and stay very still, so the frogs sometimes cannot find them, but this usually isn't really a problem. The worst problem is that, hydei cultures can grow explosively in one generation and then crash in the next. In short they are unstable.
Although I cannot claim I have all of the problems worked out, I know of two reasons that this happens. First, hydei male fertilty seems to be sensitive to higher temperatures and keeping them at over 28 degrees centigrade is probably risky. I have had cultures kept that way that are full of eggs but none hatch. I haven't done any true experiments and I haven't found anything in the literature, but am pretty confident because D. melanogaster males are also quite sensitive even if not as much.
The second reason, hydei cultures crash is because it can take a week or two at room temperature after hatching for hydei males to produce viable sperm. This is common among the larger Drosphila species. Although I haven't found data specifically referring to hydei, it seem to be a big difference from melanogaster which only takes about 10 hours after hatching at 25 degrees C.. Because of this lag in male fertility, if you put fresh flies into food medium it can be 10 days or so before the first larvae hatch out and by then the food is either dried out or gone bad and kills off the adults. What you have to do is either keep transferring them to fresh food medium or even better, mix the fresh flies with old flies so that the old males will immediately fertilize the fresh females. What I do is, mix fresh and old flies half and half with every bottle, so that the fresh males should be ready to fertilize the new females the next time.
Good luck with your hydei! You will love them when they really get going!
Also, the length of development for D. hydei is 14 days at 24 degrees C (Hess 1976)
June 2000
I had been using a ultrasonic humidifier for misting, but have now started using a high pressure misting system sold by Vivaria Projects of Amsterdam. After trying it out, I increased the number of vivariums misted by this system from 2 to 5 and am very satisfied with it. The amount of water atomized by this system is must greater that by an ultrasonic humidifier and believe it much better mimics the mist or rain in a natural environment, washing down plants, moss and glass surfaces and replacing the water in bromalid wells. The nozzles spray over an angle of 80 degrees, and one nozzle is sufficient for each of my 60x45x55cm vivariums. A friend is using a single pump for 10 vivariums and says he can probably connect more.
There are however several shortcomings with this system. First of all, although well worth it, the system is rather expensive. Secondly the system comes as a kit and requires some wiring and work on the piping. And finally, and importantly, the whole system is quite noisy. This is due to the sound of the diaphram pump itself and the vibrations caused by high pressured water in the piping. Both the pump and hosing must be securely fixed to minimize noise, and even so it it something you do not want to run at night.
ヤドクガエルのビバリウムでは霧吹きもしくは加湿は重要です。植物を茂らせるのにも、カエルを繁殖させるのにも助けになります。ぼくはしばらく野の間、超音波加湿器を愛用していましたが、1年ほど使ったら振動板が金属疲労で機能しなくなり、自動加湿は中断し、手動の園芸用の農薬散布機（巨大な霧吹き）をつかっていました。
そんな状況が長い間続く中で、知人から自分が購入しながら使っていないVivarium用に開発された噴霧器の使用を勧められました。最初は躊躇したのですが、使ってみたら性能も効果も素晴らしく、現在はみんなに薦めています。発売、開発元はオランダ、AmsterdamにあるVivaria Projectsです。輸入元は東京のワイルドスカイです。難点は結構高いことですが、販売価格は現地価格と殆ど差がないので良心的だと言えます。また、このシステムはあくまで、キットでかなりの工作をしないと設置できませんので、配管、配線作業に自信のない人は辞めた方がいいかもしれません。
仕組みですが、まず貯水槽（キットに含まれず）に水の取り出し口をつけ、配管でDiaphramポンプに水を引きます。ポンプは貯水槽の水面より低い位置に設置し、しっかり固定しないと振動で凄い騒音をたてます。固定しても結構うるさく、集合住宅での夜間使用は避けるべきです。ポンプから出た水はジョイントで分岐させ、幾つかのノズルに連結します。10個ぐらいまでならノズルは増設可能でだそうです。現在あと、5個のノズルをつけてますが、水量、水圧は充分です。ぼくは苔取り用のマグネットでノズルを固定しているので、設置場所の移動は簡単です。
ノズルの吹き出し角は80度あるので、コーナーに設置すれば、中型のケース（60cm）全体に水は行き渡ります。水は霧よりは大きい微小な水粒です。超音波加湿器の霧よりも水量が多く、手動の霧吹きを想像すればいいと思います。
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