How to get your mature koi to spawn
Vol: 418 Date:
Nov 6th 2004
The Water Gardens Gazette
1. Breeding koi in garden koi ponds .. by Ben Helm
2. Get Brett's Newsletter
3. De-Icers, Pond Filters, UV's & Pond Plants On Line
4. Admin section
1. Breeding koi in garden koi ponds .. by Ben Helm
Let me first introduce Ben Helm who has contributed this article and will be a regular contributor in future.
Ben Helm is a qualified marine biologist who has kept fish for most of his life. He has written masses of free information for the specialist aquatic and garden pond titles across the world for over 10 years and has recently written two chapters for a book on koi. He used to farm ornamental fish for a living and was head of the fish farming and aquatics dept for 5 years at Brooksby College (UK). He has appeared on BBC TV and Radio, talking about his passion for Japanese koi, ponds and fish-keeping. Ben has also lectured on ponds and aquatics to trade and consumer groups across the world and is currently the marketing and product manager for a leading brand of pond food. Ben knows the pond supplies market in the UK intimately and is able to provide reliable free information on most aquatic products. Plants are important parts of aquatic systems and algae and blanketweed are in facts types of plants discussed at great length by Ben. Ben lives in Nottingham area in UK
Visit Ben's pond keeping, breeding caring for koi website
How can I get my mature koi to spawn?
I have been a koi keeper for five years now and I haven't bought any koi for the last three years. My pond is approximately 3,000 gallons and has nine koi. They are all between three and four years old and range from 20cm to 45cm in length. Everything is running very smoothly at the moment, the filters are well matured, the fish feed well and are happy and healthy. I am now at the stage where I would like to take on a new challenge. I would like to start breeding my own koi but I'm not really sure how to go about it. I have read some books on the subject but I still feel as though I need a lot more information. Can you help me out?
It sounds as though you have a fine collection of koi that are ideal candidates for spawning. Assuming that you have a mix of both males and females, your koi will by now be sufficiently mature to spawn. There are a number of practical things you need to consider before embarking on the path of becoming a surrogate koi farmer. Furthermore, you should be aware of the limitations you are likely to face, which hopefully will temper your expectations. The koi that are in your pond will respond to environmental cues in the same way as career broodstock do in Japan, so where possible, to help you understand the spawning process, I will touch on some tricks that the professionals use when farming koi.
To breed or not to breed?
Now that you are looking to breed your mature koi, you will hopefully have taken into account the risks involved.
Many koi keepers do not wish their koi to breed, as the spawning event is quite stressful for koi. Unlike at all other times, koi are not graceful or reserved in their spawning behaviour. If males significantly outnumber ripe females then females in particular can become quite exhausted and physically damaged as the males drive and bash at the swollen females in their attempts to expel their eggs.
This can lead to loss of scales and permanent scarring and when I used to farm koi, I had regular contact with a number of koi keepers who wanted their females to be induced and stripped artificially to release their eggs in a controlled manner. Many of these females already exhibit damage from previous spawning activity. On the more positive side, you have the opportunity of increasing the number of koi in your pond, tapping into the genetic and biological potential of your own koi.
Visit Ben's pond keeping, breeding caring for koi website
What makes koi spawn?
I am a little puzzled as to why your pond full of mature, healthy koi has not already spawned spontaneously in the preceding years. They are no more likely to spawn next year by you simply wishing them to do so. Once you have identified the key spawning triggers, you will have to intervene accordingly in order to stimulate a spawning response.
Koi spawn in late spring/early summer in response to environmental stimuli which signal that their environment will provide their fry with the physical conditions and natural food supply so crucial for their good growth and survival. Even though koi are in-bred selected descendants of wild carp species, they have retained this biological clock from their ancestors, and it is something we can capitalise upon when trying to stimulate them to spawn.
Two key factors that stimulate koi to breed are water temperature and day length (photoperiod). These stimuli work in tandem to influence when koi spawn. Water temperature will fluctuate at comparable dates from year to year, whereas photoperiod is far more consistent. I.e. We know that June the 21st will be the longest day each year but that temperature will fluctuate year on year and is not as predictable as day length (especially up in Lancashire!). The overall effect of these interactions means that koi will spawn at different times all over the country (or perhaps not spawn at all).
It is the increasing day length that has the greatest effect on maturing the female's eggs, with water temperature having more of an effect towards the time of spawning. Koi are happiest to spawn at about 20 degrees C or on subsequent cooler mornings once these temperatures have been achieved. The final trigger for spawning may sound obvious, but once the females' eggs are ripe, the factor that finally causes the eggs to be released and spawning activity stimulated is the presence of males. By keeping the sexes separate, commercial farmers can prevent spontaneous spawning events, but unfortunately, in your pond, you are likely to experience (or even miss) a spontaneous flock spawn.
Problems with a flock spawn.
Besides the risk of physical damage, a flock spawn immediately limits your productivity as a koi breeder. As soon as a female koi releases her eggs into the pond, there is a 30 second window of opportunity for the sperm (which are now heavily diluted in your pond water) to fertilise the eggs. After that, as the eggs swell by taking on water, the micropyle (small duct) through which the sperm will fuse with the female genetic material will close. This will lead to an overall drop in fertility rates, having a knock-on effect for the fry numbers.
A flock spawn also impacts upon the quality of fry produced. The specimen varieties that we stock in our own ponds are the product of crosses between similar koi varieties. The probability of achieving something similar in a spawning free-for-all in a koi pond is greatly reduced. So in realistic terms, you should aim at producing viable fry that you can grow on (irrespective of their livery). Don't expect these fry to resemble any recognised varieties, as this can only really be reliably achieved by spawning known parents under controlled conditions.
Why are your koi not spawning spontaneously at the moment?
Having farmed koi for over 7 years, experience shows that you need to have complete control over all of the environmental stimuli to have a chance of being successful. By doing so, you can virtually guarantee a spawn. In a garden pond however, you have to accept the environmental conditions provided naturally, often with unpredictable results. The natural conditions will of course prove more difficult in the north of England, compared with the south. You can however, increase your chances of spawning by manipulating your pond's temperature at 2 key periods in the calendar year.
Autumn-Winter. Koi that experience a cold period (4 Degrees C or below for 1 month) have been shown to spawn more reliably the following season. Ensure your koi experience 1 month of ambient temperature through the winter.
Spring-Summer. Once you have reset their biological clock to 'zero' (by giving them a cold period), you can now increase their chances of spawning by heating the pond from mid February onwards, achieving a minimum of 15 Degree C each day. Again, experience shows that if koi experience 1000 degree days (see Boxout), they are likely to spawn. This certainly works for professional carp and koi farmers who make this strategy the backbone of their farming husbandry.
Allowing your koi to experience 1000 degree days.
The water temperature is raised gradually, held at 15 degrees C and your koi are subjected to a lengthening photoperiod.
The golden rule in maturing females is to subject them to 1000-degree days. That is, 3 days at 15 degrees C = 45 degree days and so on. A tally of degree-days should be kept to ensure that at least 1000-degree days are achieved prior to spawning. Once achieved, koi are likely to spawn. Give them a final helping hand by bringing your pond temperature up to 23 Degrees C.
Spawning time.
Once your pond approaches the 1000 Degree Days mark, you can add spawning media (soft rope/woollen mops) onto which your koi will deposit their adhesive eggs. These can then be later removed as your koi will soon help themselves to the eggs (and later on - the fry).
Fry rearing.
Even for the professional koi breeder, raising fry is the most challenging part of farming koi. This is certainly the experience for most koi keepers that experience an unplanned spawn. The short notice does not allow sufficient preparation which means that many thousands of eggs will only become hundreds of fry. Ultimately only a handful of homebred koi will reach fingerling size. For this reason, if the hobbyist is keen to breed from their collection, they must provide the eggs and fry with suitable conditions to hatch and grow out in.
Quite paradoxically, the best environment for fry to flourish is in a green, unfiltered but natural pond, full of microscopic zooplankton. It is often resistance against such an 'unsightly' pond that results in only a handful of fingerlings being produced in the same pond as the broodstock. Stocking fry into 'stew ponds' is the method used by commercial koi farmers grow on their fry in both the UK and Japan. If you have any spare clay-based land, then dig yourself a fry pond; it will certainly increase your yield.
As an encouragement, it must be remembered that each year even commercial breeders produce many thousands of very poor, low-grade fry similar in appearance to those produced by accident in koi ponds each year. The difference being that the commercial breeders start off with many more and are able to cull hard, ensuring that only those fish exhibiting good characteristics make it to market. As koi keepers, we should be thrilled with any extra home grown koi that we can produce, being loathed to cull any of them.
So in conclusion, it is a little mystifying why your mature koi have not already spawned in your pond. As one of the key factors is water temperature (a likely limitation in sunny Lancashire!), by investing in a pond heater and using it wisely and strategically, your chances of spawning koi in your own pond will increase. However, be well aware of the risks and limitations involved. We should be realistic when trying to breed koi and raise fry in the same pond, being happy to see only a handful of fry reach 2-3" in their first year, irrespective of their coloration or pattern which are likely to be disappointing.
Copyright 2004, all rights reserved. This article may be duplicated for use provided all biographical information and web links are preserved. exactly as above
2. Get Brett's Newsletter
Brett Fogle is the owner of Macarthur Water Gardens in Florida. He writes an excellent newsletter and even a daily Q&A so give him a visit and subscribe click here Subscribe to Brett's newsletter
3.The BEST low cost bio filter and UV equipment
Information on Alfagrog
Without getting too technical this means that 1 litre of Alfagrog can hold the
same amount of bacteria as 200 litres of plastic tubes. In other words a box
using plastic tubes needs to be 200 times bigger in volume than one containing
Alfagrog to get the same biological performance.
Alfagrog fantastic low cost biomedia ... buy here, search for SUPRA after clicking
Alfagrog looks a bit like cinders, it is lightweight, comes in different sizes and you can literally blow through it because it is so porous.
"The Complete Pond Solver" by Tony Roocroft
2004 Edition. Essential reading for anybody who wants or has a garden pond. Get 12 Excel pond calculators free as well as "Water Lilies and Pond Aquatics" ebook also free
Pond plants and pond supplies on line
Pond plants ... every garden pond should have some (even those small barrel ponds I discussed last time). Here are some suggestions for this season and where you can get them on line ... click the image banner below and then choose Water Plants once you get to home page
They have nice basic variety of water lilies for sale ... every
pond should have a water lily or two.
There is also a wide range of marginals too. Well worth a look Other plants available ... see the pictures at my web site by clicking the link not placed here to reduce download time
Winter is coming closer for our Northern hemisphere friends. Make sure that there is a hole in the ice covering the pond so that noxious and poisonous gases can escape.
De-Icers for ponds (even patio and indoor ponds)
These of course are simple and low cost devices and can be viewed and explored at the same site ... ie click here . One of the models offered reads as follows and this will give you an idea as to how they work.
Heats the water, keeps open an ice-free area of approximately 30" in diameter at minus 40 degrees Fahrenheit. Thermostatically controlled, which shuts off at 60 degrees Fahrenheit. Heavy-duty float will not rust, corrode or leak. Special 10" heating element. 6' heavy duty grounded wire. If tank runs dry, heating element will not burn out. Individually packed. 120 AC voltage.
You can also check here for a whole range of low cost pond products of all sorts by clicking this link http://www.practical-water-gardens.com/sitedirectory9.htm here you will also find numerous autumn pond treatment possibilities
NEW REPRINTED AND IMPROVED VERSION "The Perfect Pond Recipe Book" Unique DIY Book and Manual by Peter J May ... I am pleased to provide this space for Peter who has helped myself and my readers so much over the years. I fully endorse this book. I first got it around 1995.
"The Perfect Pond Recipe Book" is not just for those flat perfect bowling green situations. The techniques shown in my book enable you to put a pond or waterfall into any terrain.
Do take a closer look at Peter's book and information Click here and go to Perfect Pond Recipe Book Page
4. Permission To Publish and Admin section
Bona fide web masters and web site owners who have a genuine interest in helping people succeed in pond keeping are welcome to publish articles from these Gazettes subject to one simple condition. Please include in the opening to the article the following link. All you need do is copy these 2 lines of code and paste into your HTML
"http://www.practical-water-gardens.com/"
All you need to know about water gardens, ponds, pumps, bio filters and UV lights
This code will show as follows on your web page .... All you need to know about water gardens, ponds, pumps, bio filters and UV lights
Please help others
Your friends can subscribe too. Send them a copy of this Gazette and ask them to click here
unsubscribe by sending this e mail click here
(c) copyright 2003 - 2004 Tony Roocroft, All rights reserved.
Discount, special offers Gazette Readers USA only
Get a discount on products bought from this major on-line pond store in USA only Use coupon code SAVE 10 during check out Aquabead pond filters for larger bio filters and koi keepers
These world class USA-made bio filters suit larger ponds and those koi keepers looking for maximum efficiency Pond supplies catalog
Petsmart offers an extremely wide range of pond products at great prices with unbeatable support UV & bio filters ... Clean and clear water pond reviews.
Pond Filter Reviews. learn which filter and UV combo is ideal for your pond ... low cost too How to select correct pump for your own pond or waterfall
How to select your ideal low cost high performance pond and waterfall pump made easy here. You will see running cost too Freshwater Aquarium supplies catalog
Petsmart is the supplier here and trust and reliability are assured Saltwater aquarium supplies
Petsmart is the supplier here and trust and reliability are assured The Pond Professor's Blog here you can see interesting questions and answers and also see when new additions are made to the Pond Professor's main web sites The Perfect Pond Detective ... Peter J May's UK landscaping website All about koi ponds, breeding, feeding and caring Ben Helm's UK koi keeping website