As of October 2020, 159 IMMAs have been identified following the hosting of six expert workshops in the regions represented in Table 1 below. There are an additional 22 candidate IMMAs (cIMMAs) and 130 Areas of Interest (AoI). Details of all these are in the searchable database and displayed on the e-Atlas. Table 1 shows the number of IMMAs by region.
| Region | IMMA | cIMMA | AoI | Total |
|---|---|---|---|---|
| Australia, New Zealand and South East Indian Ocean | 31 | 2 | 13 | 46 |
| African Atlantic | 1 | 0 | 0 | 1 |
| Extended Southern Ocean | 13 | 1 | 7 | 21 |
| Mediterranean | 26 | 7 | 34 | 67 |
| European Atlantic | 1 | 0 | 0 | 1 |
| North East Indian Ocean and South East Asian Seas | 30 | 7 | 32 | 69 |
| Pacific Islands | 20 | 4 | 19 | 43 |
| Western Indian Ocean and Arabian Seas | 37 | 3 | 23 | 63 |
| Grand Total | 159 | 24 | 128 | 311 |
IMMA size
There is a huge range in size among different IMMAs, the largest is 431,498 km2 encompassing an area of the Pacific Ocean around the Cook Islands Southern Group in the Pacific Islands, and the smallest is 45 km2, the Akrotiri IMMA which includes small breeding caves for the Mediterranean monk seal (Monachus monachus).
Criteria used to identify IMMAs
Table 2 provides a summary of the criteria that have been used to identify IMMAs: Criteria C, Key Life Cycle Attributes, which includes migration routes, reproductive areas and feeding areas has been the most frequently used criterion, and Criterion D, Special Attributes has been the least frequently used.
| Criteria | Species or Population Vulnerability
A | Distribution or Abundance
B | Key Life Cycle Attribute
C | Special Attributes
D |
|---|---|---|---|---|
| IMMAs | 129 | 111 | 132 | 73 |
| %of Total | 29 | 25 | 30 | 16 |
Figure 1 shows the number of IMMAs broken down by the sub-criterion applied. After Criterion A (Species or Population Vulnerability (23%), the most frequently used sub-criteria were C1 (Reproductive Areas) (18%) and C2 (Feeding Areas) (16%).
Figure 1 – Number of IMMAs broken by subcriteria
Qualifying Species in each IMMA
The documentation for each IMMA includes a list of the qualifying marine mammal species that occur and that are fundamental to satisfying each criterion used in the IMMA identification. Supporting species are marine mammal species that occur within the IMMA but which are not fundamental to satisfying the criteria. Figure 2 shows the number of qualifying species listed for each IMMA. The majority were identified on the basis of one or two qualifying species.
Fifty-eight different marine mammal species have been used as the qualifying species for an IMMA. As shown on Figure 3, humpback whales (Megaptera novaeangliae), dugongs (Dugon dugon) and spinner dolphins (Stenella longirostris) were the most commonly represented species.
Figure 2 – Number of qualifying marine mammal species listed for each IMMA
Figure 3 – Qualifying marine mammal species used to satisfy the IMMA criteria (only species listed as qualifying species more than 4 times are shown)
