For many years New Zealanders had unrestricted use of large stretches of seashore and can be forgiven if they laboured under a myth of super-abundance. More recently it has become increasingly apparent that there is not an endless supply of coastal land nor are the undeveloped areas necessarily to remain open to the public. These changes are discussed along with the remedial action taken and the difficulties encountered.
To establish whether poisoning programs affect non-target density, the null hypothesis that density does not decline on poisoned sites needs to be tested. However, where no statistically significant reduction in density is found, there is some probability that a biologically significant reduction has been overlooked. The probability that such an error has occurred (a Type 2 error) depends on the effect poisoning has on non-target density, the precision with which the reduction is assessed, and the number of poisoning operations sampled.