Like all of the other Sporting breeds, Curlies were originally developed to do a job in the field. Our breed is unique among the retrievers in that its original job included quite a bit of upland work, whereas the other retriever breeds were almost always used on waterfowl. Upland work requires that a dog be more energetic and do more work away from the hunter (as well as physical differences - more on that in a future article) than waterfowling, but in a breed that is expected to do both one doesn't want a dog that is too energetic or too independent. So, the Curly temperament is unique as well.
Correct Curly temperament is one that best fits the breed's original job, or rather jobs. I'll take them one at a time, beginning with waterfowl. This dog needs to be able to lay quietly in a blind, maybe for hours, waiting for birds to come in, and then not go bonkers when birds are circling and talking up above. Then, provided the hunter hits something, the dog must have the energy & desire available to swim out, frequently in freezing water, and retrieve the downed bird, and maybe chase a cripple all over. The dog must also have the trainability to learn to handle to the bird should it be needed, and the willingness to work with the hunter even from a distance across water. After all that excitement, the dog must be willing to lie down in the blind and be quiet again.
Waterfowl hunting also includes jump shooting, which requires that a dog walk quietly next to the hunter as he sneaks a pond and remain steady to at least shot if not completely steady. Or, they might lay under camo tarps in a field waiting for geese to come and feed, where again the dog needs to be quiet for quite some time and not interfere when the hunter goes to take his shot. So, the ideal "duck dawg" is one that can remain quiet during long boring hours of nothing, but will become at least energetic enough to retrieve birds, possibly at a long distance from cold water. The dog needs to be trainable enough that it will not break or make noise at inopportune times and be willing to take direction from a distance away over water.
Upland hunting requires an almost completely different dog. This dog must have the desire & energy to hunt ahead of the hunter in gun range in an active and relatively controlled manner. When a bird is flushed, the dog should at least be under enough control that he is not in danger of being shot and should the bird be missed, the dog should come back without much shouting (ideally the dog sits to flush and doesn't move until commanded to retrieve or to continue hunting). This goes on for hours and may involve many flushes that require self control, or may involve very few birds found. In the former case, the dog must have enough trainability to remain under control no matter how exciting things get, and in the latter the dog must have enough desire to keep hunting even when pickings are slim. Upland dogs should also be able to run a blind.
So, both types of hunting require that the dog be trainable and biddable enough to be under control when things get exciting, to come back when called, to take direction from a distance when needed. In my opinion, a waterfowl dog needs to be more "fetchy" and an upland dog needs to be more "birdy", but both do need to have the desire to find and retrieve birds even when the going gets tough. Upland work requires more independence and self-confidence, but waterfowl dogs also need these characteristics in order to be useful at running down a cripple or to continue a long swim. Waterfowl dogs are sprinters, upland dogs are marathon runners.
Traits that a working retriever needs no matter what type of bird he is hunting include pain tolerance, courage, heat and cold tolerance, ability to handle stress, forgiveness, smarts and problem solving ability. Left over from the days of being a game warden's dog, the Curly is also somewhat of a one man/woman dog and generally makes friends slowly.
What does this mean to a breeder, particularly one that doesn't hunt? Most Curly breeders these days do not hunt, and for the most part never did. The next best thing - active participation in upper level field events - is even rarer among Curly breeders. But even those that do shows only can still select for correct temperament if they choose to, by using dogs that show correct characteristics in day-to-day life. These would be dogs that are not "babies" when it comes to things like nail trimming or a minor injury; dog who do not put up a huge fight when told to do something they don't want to do, and then do not hold a grudge later; dog that travel well and don't go off their feed, get the runs or refuse to show simply because they didn't sleep in their own beds the night before.
On the other hand, a Curly with correct temperament may refuse to "show" because he has not had enough experience with allowing strangers to touch him without a proper greeting period. This dog will not be shy in any way, he will just be unwilling and showing distaste for the whole thing. Many judges have told me that they didn't do for such and such dog because "he just wouldn't show", thereby showing their ignorance of what a Curly is. Very few Curlies will "show" for any period of time, either because they are insulted by having to allow a stranger to touch them, or because they have done it enough times that it becomes very boring. Curlies should also be smart, and there isn't a whole lot in a dog show ring to engage their interest once they have been there a few times.
"Smart" can be difficult to live with if the dog is in a non-active home. A Curly with the correct intelligent, active, problem-solving temperament can be a royal pain to deal with if it doesn't get regular exercise for its mind and body. These dogs learn to open doors and crates, figure out daily routines to their advantage and can be very destructive, all in a quest for something interesting to do! Curlies with correct temperaments are not soft, mellow, laid back or any of the other descriptive terms used for easy to live with dogs.