Wow! I am totally overdue for an update! So today’s topic is going to be…
Mercury in cuttlebone. A breeder/client/friend of my recently told me that people are discussing a concern of mercury levels in cuttlebone. Cuttlebone is the bone from the cuttlefish that is often sold in pet stores for use as a calcium supplement. There has been discussion of excess mercury levels in birds and this was traced back to the cuttle bone supplement. As I had not heard of this concern before, I posted this question to the veterinary experts available through a veterinary networking system that I belong to. Multiple experts in the field of avian medicine replied, which I was very appreciative of. In the opinion of all whom responded to my question, the answer was no…mercury levels in the cuttlebone are not high enough to be a concern. A couple of interesting points were brought up in the conversation.
1) Cuttlefish may eat mercury containing prey, however the majority of the mercury is located in the GI tract, and then possibly the muscle. The least amount available is in the bone.
2) Cuttlefish do not live long enough to accumulate enough mercury to be a concern.
I also found a good article online that has an complete analysis of cuttlebone:
I did a quick internet search just to see what the general public thought on this topic and it does seem to be a topic of interest. In two different online conversations, the thread was started by someone who has gone to a petstore and someone at the petstore suggested there was mercury in the cuttlebone.
After doing my research, I decided to find out if my laboratory tests for mercury. In the past, I have had need of lead and zinc testing, two common heavy metal toxicities seen in birds. But never mercury. The response was that they can test for it and they require 1 ml of whole blood for the test. That is a large amount of blood for most birds. I would not even be able to test a budgie or parrotlet for it as they only have approximately 3 ml of blood in their entire body. But it is good to know this is an option for larger birds if I ever think I am being presented with a mercury toxicity.