When talking about problem behaviour during canine adolescence, most people think about male dogs and the effects on their behaviour of increasing testosterone levels, notably at around 9 months of age. They can become rather pushy and obnoxious at this age under the influence of increasing testosterone (it only lasts a few months though). But many people seem unaware of possible changes in female canine behaviour.
One of the biggest factors I have noticed is how often females can start to become anxious shortly before their season starts. I don’t know what the frequency of this is, or specifically why this is, but it is something I see reasonably often.
About a month before a female season, they can show behavioural changes and increasing anxiety. Whether this is to do with hormone changes, or whether it is something else, I don’t know. It could be that male dogs start showing more interest and if she is not that confident, this may overwhelm her, increasing her anxiety. It might be that the hormone changes make her feel unwell reducing her ability to cope, as can be the case with human females.
However, it has been said that canines can go through second sensitive periods, often around 6-10 months of age, and it might just be that this coincides with a season. This second sensitive period is said to have an evolutionary purpose. It is at this age when free living dogs may migrate from their family groups to find mates. If you are migrating from the safety of your family group, it is an evolutionary advantage to be more fearful as this could keep you safer.
So, if you notice your female adolescent starting to become anxious, please listen to this behaviour. It is reasonably common. You should protect your dog from being unduly anxious by keeping her away from anxiety eliciting situations. Give her a break and let her decide what she can cope with. If she doesn’t want to go out on a walk, then try brain games in your garden or home.
If during her season her behaviour changes further (guarding items, becoming very lethargic and quiet) do be sure to discuss this with your vet. Sometimes females cache and guard items (an evolutionary advantage in a free running pregnant dog as resources are important if raising a family). If you see aggressive or lethargic behaviour develop you definitely should discuss with your vet as serious complications such as pyometra need to be ruled out. If your female is otherwise healthy, you may find a hormone treatment that your vet can prescribe that would stop the guarding behaviour by changing the hormones that initiate this behaviour. In addition, careful management to ensure she can't take items and guard them is important and sensible (it's not the ONLY answer though. Lack of perceived resources in a dog that thinks she is pregnant can be extremely stressful). This behaviour tends to start towards the end of the season and beyond, especially if she has gone into a phantom pregnancy.
Don’t suffer in silence, talk to your vet first. The more this behaviour gets practised, the more likely it is to become a habit and then you may need behaviour therapy to resolve the guarding behaviours.