The popular press frequently reports that coat colour bias negatively impacts shelter adoption rates for black domestic dogs. This phenomenon, commonly called ‘black dog syndrome’ (BDS), reportedly increases the likelihood of euthanasia for black dogs and negatively affects the length of black dogs’ time to adoption. While organisations may focus on BDS and ways to promote black dogs, it is possible that the influences of other important factors, such as sex, age and breed, may be overlooked. To evaluate the veracity of BDS and examine the impact of various phenotypic traits on shelter outcomes, we analysed four years of intake and outcome data from two animal shelters in the Pacific Northwestern United States. Results indicated that the average length of availability for adoption (LOA) for black dogs was not significantly longer than that for other coloured dogs, nor was the rate of euthanasia of black dogs significantly higher than average. On the other hand, age and breed group were consistent predictors of shelter outcomes across the two shelters. Older dogs tended to have longer LOA and to be euthanised at rates higher than expected. Bully breeds had significantly longer LOA in both shelters and, compared to other breeds, were euthanised at higher than expected rates. The methods implemented in this study could be utilised by other shelters to inform intake and marketing strategies.