Mortality rates provide MAC, the industry and hobbyists with a simple, equitable, transparent and marketable system to evaluate whether marine aquarium organisms are maintaining the best practices in the collection, handling, holding, husbandry and transport that ensure the optimal health of marine aquarium organisms. MAC had substantial input from all stakeholder groups and the entire marine aquarium industry chain of custody regarding the level of mortality that should no longer be considered reasonable and responsible.

The MAC international Standards sets the allowable limits of marine aquarium organism mortality at the species level at 1 percent dead on arrival (DOA) and 1 percent dead after arrival (DAA) per species and per shipment for each link in the chain of custody. The typical links in the chain of custody occur between

1) the collection area and the collector/fisher;
2) the collector/fisher and the exporter;
3) the exporter and the importer; and
4) the importer and the retailer.

DOA refers to organisms that are no longer alive upon receipt and opening of the shipping container at the beginning of the acclimatization period. DAA refers to organisms that are no longer alive from acclimatization through the holding period until the organism is packed for onward shipping. If in a shipment containing 12 different species of marine aquarium organisms, one species has a mortality rate of over 1 percent; it is the only part of the shipment to be affected by loss of MAC Certification. The other species’ batches can continue on in the chain of custody as being MAC Certified.