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MOSQUITO FISH Powered By Docstoc
					HOW TO OBTAIN MOSQUITOFISH CONTINUED                      longer periods of time. Unlike chlorine,
                                                          chloramines do not dissipate from water             Facts about
   tainer unless the air space is equivalent to
                                                          left standing overnight. To be completely
   the water space in the container. Large plas-
                                                          safe, always pre-treat your water before
   tic containers, those with large surface ar-
                                                          adding fish to your pond no matter how
                                                                                                        MOSQUITO FISH
   eas, are most practical. Keep the containers                                                              In California
                                                          little you add. Chloramine residuals in
   out of the sun light during transport.
                                                          treated water should be below 0.1 mg per
INTRODUCING FISH TO YOUR POND                             liter. For more information visit
   Fish should be introduced into the pond as
   soon as possible. To avoid shock when intro-        DISTRICT OBJECTIVE
   ducing fish into the pond, it is recom-
                                                          To provide an effective abatement pro-
   mended that you equalize the water in your
                                                          gram primarily directed toward the control
   bucket of fish. You can achieved this by ei-
                                                          or prevention of mosquito production.
   ther adding some pond water to the bucket,
                                                          Elimination of unsupervised water im-
   or place the bucket into the pond for a short
                                                          poundments is an essential step to safe-
   time to allow the two water temperatures to
                                                          guard against mosquito problems.
   The San Mateo County Mosquito Abatement
                                                       DISTRICT APPROACH
   District has an ongoing program of inspec-
                                                         Under the California Health and Safety
   tion and stocking of all known ponds in the
                                                         Code, mosquito abatements are granted
   District. This service is done at no additional
                                                         powers to take all necessary and proper
   cost to the residents. If you have a pond and
                                                         steps for the elimination and extermina-
   would like fish , please call the District office
                                                         tion of mosquitoes. To implement the
   at 650.344.8592 to set up a delivery.
                                                         program objectives, district personnel
CHLORAMINES                                              make routine inspections of countless
  Tap water in San Mateo County is treated               mosquito sources, such as ditches, chan-
  with chloramine (and not chlorine). Although           nels, lagoons, drain lines, marshes,
  these chemicals are toxic to fish, shellfish,          creeks, lakes, flood control basins, utility
                                                         vaults, catch basins, and fish ponds.             San Mateo County
  reptiles and amphibians, they do not affect
                                                                                                          Mosquito Abatement
  mosquitoes.                                            When mosquito production is found, ap-
                                                         propriate action is taken to control or             1351 Rollins Road
   Chloramines are chemicals which contain                                                                 Burlingame, CA. 94010
                                                         eliminate the problem.
   chlorine and ammonia. Chloramines are
   considered safer for drinking water than
   chlorine because they reduce the formation
                                                                     San Mateo County
   of hazardous by-products and keep the bac-                  Mosquito Abatement District                  Tel: 650.344.8592
   teria killing disinfectant in the pipelines for                 1351 Rollins Road
                                                                 Burlingame, CA. 94010
                                                  POND ENVIRONMENT                                           Bird baths or plastic wading pools are seldom
                                                   Under favorable conditions, mosquito fish, in Cali-       suitable as fish ponds. Shallow water does not
                                                   fornia, will live 2 to 3 years. Occasionally a large      provide adequate protection from elevated
                                                   die-off may occur during the winter months when           temperatures or predators. In addition, high
                                                   low temperatures adversely affect the fish. To            temperatures enhance algal growth and de-
                                                   avoid fish mortality, supplementary feeding               plete the amount of oxygen that water can
  The mosquito fish (Gambusia affinis), a          should be done with caution. Overfeeding may              retain.
  close relative of the guppy and a member         enhance bacterial growth and cause rapid fouling          Limited amounts of algae can be beneficial to
  of the family Poeciliidae, is used exten-        of the water, a condition that may be lethal to fish.     mosquito fish. An over-abundance of algae, an
  sively throughout the world by mosquito          Also, artificially fed fish make poor mosquito            amount that impedes light penetration, should
  abatement and vector control agencies for        predators. Although mosquito fish prefer the shel-        be removed. Removal can be achieved by
  control of mosquito larvae. Mosquito fish        ter of rocks, overhanging plants, and banks, they         cleaning the pond or using an application of
  can survive wide temperature variations          do not thrive in heavily shaded ponds. Normally,          an appropriate algaecide. If an algaecide is
  that range from below 0º C. to above 35º         the fish seek-out a sunny section of a pond and           selected, care must be practiced to specifi-
  C. (32º F. to 97º F.). It has been observed      orient themselves to shallow areas with sub-              cally follow the directions. An overdose of the
  that fry (young fish) are more tolerant of       merged vegetation, locations often frequented by          chemical could be fatal to the fish.
  temperature variations than mature fish.         mosquito larvae and pupae. It is recommended
  The adaptability and hardiness of the mos-                                                               OPTIMUM POND CRITERIA
                                                   that some aquatic vegetation be provided in
  quito fish, coupled with its ability to pro-                                                               1. Ponds should have a minimum 6 inch
                                                   ponds as shelter since mosquito fish are cannibal-           water depth
  duce large numbers of fry during their life-     istic on smaller fish. In large ponds, the mosquito       2. Pond edges should have steep sides
  time, has made the mosquito fish a valu-         fish will sometimes avoid the shaded areas even           3. Rocks and aquatic vegetation should be
  able biological control agent.                                                                                present
                                                   though numerous mosquito larvae are present.              4. Provide a circulation pump to enhance
REPRODUCTION                                       This may occur if the fish are fed artificially or if        water quality
                                                   there is an abundance of naturally occurring food         5. Pond lining. If new cement, allow several
  Mature females range from 2 to 2.5 inches                                                                     weeks to leach-out lime. Rinse the pond
  in length while the males seldom exceed          in other areas of the pond. During the colder
                                                                                                                several times, and fill with fresh water.
  1.5 inches. Gambusia are livebearers             months, fish become lethargic and feeding activity           After 48 hours, request mosquito fish for
  (ovoviviparous), better adapted to begin         is reduced. Commercial fish food may be used                 the pond
  the struggle for existence than fish             sparingly as a dietary supplement when mosquito
                                                                                                           HOW TO OBTAIN MOSQUITOFISH
  hatched from eggs. Under favorable condi-        larvae are not present in the water.
                                                                                                             The San Mateo County Mosquito Abatement
  tions, the fry (newly born fish) reach sexual    Normally 6 to 10 fish are sufficient to stock an
                                                                                                             District provides free mosquitofish to the pub-
  maturity in 6 to 8 weeks. The females, in a      average size pond. The high reproductive poten-
                                                                                                             lic and are normally available from April
  season, may bear 3 to 4 broods, the first of     tial of the mosquito fish will overcome future prob-
                                                                                                             through October. Call our office at
  which may number only a few fry. At sex-         lems with mosquito larvae. Where large larval
                                                                                                             650.344.8592 to schedule a deliv-
  ual maturity, a female may produce from          mosquito populations exist, it may be necessary
                                                                                                             ery.Transportation of fish can be critical. Glass
  60 to 100 fry in a single brood. The repro-      to clean the pond or request your local mosquito
                                                                                                             and metal containers rapidly conduct heat and
  ductive efficiency of the female declines        or vector control agency to treat the pond to de-
                                                                                                             in some cases may be toxic to the fish being
  with age, the broods becoming smaller as         stroy mosquito larvae with environmentally safe
                                                                                                             transported. Avoid sealing the selected con-
  the reproductive period progresses.              insecticides prior to planting mosquito fish.