Ticks on a dog are almost always caster bean ticks that just need to be removed. Caster bean ticks lose the ability to find a host when the temperature drops below 7 °C. If the dog has ticks when it is significantly colder outside, it may be brown dog ticks.
High levels of infestation in the house and ticks (especially blood-filled, gray females) on walls and ceilings may be brown dog ticks. Ticks that are found on dogs that have been imported from or returned from a vacation in the South, could be brown dog ticks.