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"Ready, Set, Fish"

by Mark Lauch

Introduction of fish stock into any culture system is a very exciting and critical phase in overall operations management. Following are considerations for those who have selected a specific species for culture and are ready to purchase their fish.

Selecting a farm or broker to purchase seed stock from requires research. The Aquaculture Buyers Guide is a good reference for identifying potential sources and it is available on-line. Identify and contact facilities which culture the species you’ve selected.

Be sure to inquire about availability, price, method of delivery, rearing system, feed type, customer references and current health certification and get a feel for their overall customer service. Don’t just inquire about the fish, ask about their staff and ability to deliver, too.

Remember, price is not everything! I have knowingly paid a little more for the security of dealing with a vendor I’m comfortable with and in whom I have confidence. Working toward a long term relationship with a reputable fish vendor is important.

Many states require permits for aquaculture plus permits for importation, transportation and/or stocking of fish. Usually a health certification from the farm-of-origin is also requested.

Certifications allow officials to see what vectors may potentially enter a specific state or region. The function is to mitigate against introduction of new or specific organisms but does not preclude all potential pathogens.

Even with certification you could potentially introduce pathogenic organisms with your new fish if they already exist within your state and/or regional locale.

After submitting the health certification, contact your state’s permitting agency and get their feedback. Many potential pathogens exist naturally and only become a problem when fish are stressed (i.e., during harvest, holding, transportation or stocking). A lot can occur from the point of sale to introduction into your culture system.

After choosing a vendor and procuring permits you are ready to order and schedule delivery. Schedule delivery only when you are sure your system is ready. The health and survivability of the fish you are purchasing depends upon it. Make sure all mechanical and biological components are functioning correctly.

Flow rates, aeration, biological filtration, temperature and water chemistry parameters should all be within the life history requirement range for the intended culture specimen.

Delivery during abnormally hot or cold spells is discouraged to reduce incidence of shock.

Upon arrival, inspect fish for signs of stress and/or disease. This should be done before unloading or accepting delivery.

Discoloration of skin or gills is a sure sign of stress. Redness around the mouth in catfish indicates potential mortality. Look into the holding tanks for dead or dying fish, excessive scale slough and fish activity. Fish should be upright, evenly dispersed, breathing normally and not gasping for air.

Physically inspect a few fish. Look at the gills for proper coloration, structure and visible parasites or damage. Whitened or dull pink gills could indicate problems or stress. Inspect body and fins for redness or lesions. Irregularities should be noted and questioned immediately.

Caution: Be direct but not overbearing. Transporters often spend many hours on the road and deserve, as well as command, respect. A good hauler may tell you if he has experienced problems on the road. An irritated transporter may tell you something else. Be respectful and look toward building a lifelong relationship with the farmer and/or transporter! Joke around and have a cold beverage or two on hand

Large farms often contract-out the hauling of fish. Transporters are your link to information about the fish you purchased and/or any potential “fishy” problems. They truly are a wealth of knowledge. If you see problems with the fish but don’t get answers that satisfy you, contact the farm of origin before unloading! This way both you and the

transporter have options. I have rejected fish, seen apparently sick fish recover overnight and been guilty of losing perfectly healthy fish following delivery. Never cry wolf and always keep a cool head in communicating with all involved parties. In my eight years of brokering fish, I have found that good communication skills save money, time and headaches.

Following visual inspection check your systems preparedness again. Most importantly, compare dissolved oxygen, pH and temperature measurements. Ideally, all parameters should fall within a couple of points. If they do not, acclimate fish by mixing water either in the hauling vat or another separate container. Never allow transported water to be introduced into the culture site! It’s just good preventative maintenance to keep it out.

If fish are transported to culture tanks via nets, try to avoid net contact with the culture water. Prevention is key in the success of any bio-security program. Any items which may have incurred cross-contamination should be isolated and disinfected.

If you suspect the fish of having incurred stress or are carrying external or gill parasites, a simple salt bath can do wonders. Non-iodized, (i.e. agricultural or water softening) salt is cheap, readily available and relatively safe. Check with the farm of origin for recommendations as they have a vested interest as well. Isolate the fish during this process if possible and, if you are doing aquaponics, be sure not to introduce salt to your culture water because even small concentrations of sodium can be harmful to your plants.

Most often fish do incur a minimal amount of stress from transportation and tend to recover quickly. Chronic problems are rare but possible. If something has gone terribly bad fish loss can peak within 1-24 hours or be sustained over a period of one to two weeks, depending on the causative agent.

The fish suppliers and haulers I have worked with over the past eight years have always made good. This is due to having not cried wolf and good communications skills.

Generally, an overage of 5-10% is added to the order to cover potential loss. When things go right, loss rarely exceeds the overage.

As a last note, deliveries are always subject to acts of nature and time. Harvest, purging and transportation rarely allow for a delivery to occur at, let’s say, exactly 1:32 p.m. on Friday. Allow at least a 1/2 days variance either way and be patient. It is less stressful for you and the fish once they arrive.