Indicator name

Red List Index

What does this data layer represent?

The Red List Index (RLI) shows changes in the overall extinction risk of sets of species over time, and relates to the rate at which species move through IUCN Red List categories towards or away from extinction. The RLI is calculated from the number of species in each Red List category (Least Concern, Near Threatened, Vulnerable, Endangered, Critically Endangered, Extinct), and the number changing categories between assessments as a result of genuine improvement or deterioration in status (category changes owing to improved knowledge or revised taxonomy are excluded). When the Red List Index is downscaled to show national and regional trends, each species is weighted by the fraction of its distribution occurring within the country or region. The resulting national indices show how well species within the groups included (currently birds, mammals, amphibians, corals and cycads) are conserved in the country or region relative to its potential contribution to global conservation of these groups.

What does a trend in this indicator tell us?

For the global Red List Index, a value of 1.0 equates to all species being categorized as Least Concern, and hence that none are expected to go extinct in the near future. A Red List Index value of zero indicates that all species have gone extinct. Higher values indicate lower extinction risk (i.e., higher survival probability) of the species group. A downwards trend in the graph line (i.e. decreasing Red List Index values) means that the expected rate of species extinctions is increasing i.e. that the rate of biodiversity loss is increasing. For national indices in which each species is weighted by the fraction of its range in the country, the index varies from 1 if the country has contributed the minimum it can to the global RLI (because all species in the country are globally Least Concern) to 0 if the country has contributed the maximum it can to the global RLI (all species in the country are globally Extinct or Possibly Extinct). Annual change of the RLI as shown on the dashboard is the difference between RLI values in the first year for which the index is available, and the most recent year for which index values are available, divided by the number of intervening years. Negative values indicate that species are slipping closer to extinction whereas positive values indicate that species are becoming less likely to go extinct. Values close to 0 indicate slower changes in extinction risk whereas larger values indicate greater changes in extinction risk.

How was the indicator developed?

RLI is a measure of trends in survival probability (the inverse of extinction risk) for sets of species. The methods are described in Butchart et al. (2004, 2005, 2007 and 2010), and Hoffmann et al. (2010).

The aggregated RLI is the mean of modelled RLIs for multiple taxonomic groups. The number of non-Data Deficient extant species for each taxonomic group included in this calculation (and the years for which data are available) were 9,785 birds (1988-2008), 4,555 mammals (1996-2008), 4,416 amphibians (1980-2004), 704 warm water reef-building corals (1996-2008) (only warm water reef-building species) and 337 cycads (2003-2014) (Butchart et al. 2004, 2005, 2007 and 2010). See Table 1 for the number of species within each taxonomic group used to calculate the RLI for each country or territory. The RLIs were linearly interpolated and extrapolated for each taxonomic group for the years between data points, with a slope equal to the distance between the two closest data points (except corals). Due to extreme coral bleaching after 1996, corals were not extrapolated linearly. The average of the rates for the other taxonomic groups were used as the rate of coral decline before 1996. See Butchart et al. (2010) for more information.

National indices are calculated as: RLI(t,u) = 1 - [(Ss(W(t,s) * (rsu/Rs)) / (WEX * Ss (rsu/Rs)) where t is the year of comprehensive reassessment, u is the spatial unit (i.e. country), W_((t,s)) is the weight of the global Red List category for species s at time t (Least Concern =0, Near Threatened =1, Vulnerable =2, Endangered =3, Critically Endangered =4, Critically Endangered (Possibly Extinct) =5, Critically Endangered (Possibly Extinct in the Wild) =5, Extinct in the Wild =5 and Extinct =5), WEX = 5 is the weight for Extinct species, r_su is the fraction of the total range of species s in unit u, and R_s is the total range size of species s. See the UN SDG indicators metadata here for more information.

Table 1. The number of species within each taxonomic group used to calculate the RLI for each country or territory.

Country	Mammal	Bird	Amphibian	Coral	Cycad	Total
Afghanistan	133	402	9	0	0	544
Albania	91	271	17	4	0	383
Algeria	108	302	10	4	0	424
American Samoa	26	49	0	286	0	361
Andorra	67	155	7	0	0	229
Angola	333	935	133	0	2	1403
Anguilla	30	97	1	55	0	183
Antarctica	26	52	0	0	0	78
Antigua and Barbuda	31	67	2	56	0	156
Argentina	402	981	170	0	0	1553
Armenia	90	260	8	0	0	358
Aruba	33	49	1	13	0	96
Australia	334	732	222	482	74	1844
Austria	85	232	19	0	0	336
Azerbaijan	106	314	12	0	0	432
Bahamas	38	237	4	58	3	340
Bahrain	24	110	1	107	0	242
Bangladesh	185	627	43	9	1	865
Barbados	34	67	1	56	0	158
Belarus	75	229	12	0	0	316
Belgium	78	230	16	0	0	324
Belize	164	491	39	58	3	755
Benin	205	586	44	10	1	846
Bermuda	28	27	0	26	0	81
Bhutan	167	647	32	0	1	847
Bolivia	424	1424	267	0	1	2116
Bonaire, Sint Eustatius, and Saba	37	55	0	62	0	154
Bosnia and Herzegovina	90	248	18	3	0	359
Botswana	173	544	50	0	0	767
Bouvet Island	27	38	0	0	0	65
Brazil	706	1824	882	18	5	3435
British Indian Ocean Territory	27	26	0	334	0	387
British Virgin Islands	28	66	5	55	0	154
Brunei Darussalam	176	421	65	0	1	663
Bulgaria	88	305	17	0	0	410
Burkina Faso	157	470	34	0	0	661
Burundi	199	654	45	0	0	898
Côte d'Ivoire	279	690	99	10	0	1078
Cambodia	203	543	62	171	5	984
Cameroon	376	910	213	10	0	1509
Canada	206	470	51	0	0	727
Cape Verde	29	41	0	11	0	81
Cayman Islands	32	67	2	60	1	162
Central African Republic	271	729	87	0	1	1088
Chad	149	552	34	0	1	736
Chile	163	415	57	45	0	680
China	630	1296	374	130	20	2450
Christmas Island	29	31	0	106	0	166
Cocos Islands	26	20	0	109	0	155
Colombia	528	1893	776	84	18	3299
Comoros	34	87	0	316	1	438
Congo	271	663	95	5	0	1034
Congo DRC	490	1143	241	0	7	1881
Cook Islands	27	59	0	180	0	266
Costa Rica	244	817	191	84	2	1338
Croatia	100	278	20	4	0	402
Cuba	62	269	61	61	6	459
Curaçao	37	59	0	62	0	158
Cyprus	35	181	3	3	0	222
Czech Republic	72	216	20	0	0	308
Denmark	66	227	13	0	0	306
Djibouti	92	324	6	243	0	665
Dominica	36	82	4	57	0	179
Dominican Republic	47	226	37	58	2	370
Ecuador	405	1609	493	24	6	2537
Egypt	113	331	10	310	0	764
El Salvador	164	477	34	21	1	697
Equatorial Guinea	197	487	93	10	0	787
Eritrea	114	549	19	314	0	996
Estonia	56	230	10	0	0	296
Ethiopia	285	815	67	0	0	1167
Falkland Islands (Malvinas)	34	101	0	0	0	135
Faroe Islands	23	61	0	0	0	84
Fiji	31	123	2	416	1	573
Finland	58	241	5	0	0	304
France	153	439	34	390	0	1016
French Guiana	230	683	112	0	0	1025
French Polynesia	29	104	0	189	0	322
French Southern Territories	27	64	0	313	1	405
Gabon	208	596	92	10	0	906
Gambia	140	488	32	10	0	670
Georgia	103	281	13	0	0	397
Germany	99	280	21	0	0	400
Ghana	275	692	83	10	1	1061
Gibraltar	50	164	10	4	0	228
Greece	110	301	22	4	0	437
Greenland	32	75	0	0	0	107
Grenada	40	67	3	57	0	167
Guadeloupe	18	128	4	0	0	150
Guam	26	39	0	255	1	321
Guatemala	236	687	144	75	6	1148
Guinea	275	690	95	10	0	1070
Guinea-Bissau	147	459	35	10	0	651
Guyana	269	826	152	0	1	1248
Haiti	46	217	53	60	2	378
Heard Island and McDonald Islands	23	47	0	0	0	70
Honduras	231	691	127	59	6	1114
Hungary	77	236	16	0	0	329
Iceland	31	87	0	0	0	118
India	433	1219	273	371	7	2303
Indonesia	708	1692	384	621	7	3412
Iran	197	430	23	119	0	769
Iraq	92	338	6	104	0	540
Ireland	49	185	3	0	0	237
Israel	107	306	8	4	0	425
Italy	112	315	41	4	0	472
Jamaica	51	213	21	60	0	345
Japan	141	365	57	461	1	1025
Jordan	75	245	6	0	0	326
Kazakhstan	175	418	13	0	0	606
Kenya	387	1058	106	279	4	1834
Kingdom of the Netherlands	90	249	14	55	0	408
Kiribati	25	57	0	363	0	445
Kuwait	39	179	0	104	0	322
Kyrgyzstan	87	310	2	0	0	399
Laos	244	710	117	0	5	1076
Latvia	59	227	13	0	0	299
Lebanon	76	227	8	4	0	315
Lesotho	92	322	25	0	0	439
Liberia	219	553	70	10	0	852
Libya	80	219	4	4	0	307
Liechtenstein	66	144	9	0	0	219
Lithuania	60	224	12	0	0	296
Luxembourg	55	143	14	0	0	212
Madagascar	245	259	310	341	1	1156
Malawi	206	634	86	0	1	927
Malaysia	338	684	247	584	3	1856
Maldives	28	35	0	248	0	311
Mali	161	539	32	0	0	732
Malta	19	25	2	2	0	48
Marshall Islands	24	44	0	342	0	410
Martinique	15	117	3	45	0	180
Mauritania	122	473	14	10	0	619
Mauritius	29	75	0	325	0	429
Mayotte	29	40	0	316	1	386
Mexico	523	1070	373	92	49	2107
Micronesia	28	71	0	427	0	526
Moldova	68	236	13	0	0	317
Monaco	44	40	6	3	0	93
Mongolia	137	355	6	0	0	498
Montenegro	75	234	15	0	0	324
Montserrat	33	51	1	56	0	141
Morocco	125	328	11	4	0	468
Mozambique	267	720	83	326	14	1410
Myanmar	362	1050	128	334	4	1878
Namibia	220	616	56	0	0	892
Nauru	24	41	0	332	0	397
Nepal	200	777	48	0	1	1026
New Caledonia	39	151	0	393	1	584
New Zealand	48	233	4	13	0	298
Nicaragua	225	686	75	78	1	1065
Niger	136	486	22	0	0	644
Nigeria	313	881	113	10	1	1318
Niue	26	49	0	192	0	267
Norfolk Island	34	66	0	62	0	162
North Korea	93	275	17	0	0	385
Northern Mariana Islands	27	48	0	265	0	340
Norway	80	246	6	0	0	332
Oman	73	226	3	180	0	482
Pakistan	212	638	20	82	0	952
Palau	28	49	1	431	1	510
Palestinian Territory	86	234	6	2	0	328
Panama	271	879	206	92	12	1460
Papua New Guinea	289	763	268	566	7	1893
Paraguay	187	685	91	0	0	963
Peru	526	1854	588	0	9	2977
Philippines	231	574	108	593	6	1512
Pitcairn	23	46	0	60	0	129
Poland	85	248	17	0	0	350
Portugal	96	284	19	1	0	400
Puerto Rico	40	196	20	58	3	317
Qatar	30	129	0	107	0	266
Réunion	29	59	0	299	0	387
Romania	96	286	18	0	0	400
Russian Federation	313	671	33	0	0	1017
Rwanda	236	697	52	0	0	985
Saint Barthelemy	1	33	0	0	0	34
Saint Helena	44	81	0	0	0	125
Saint Kitts and Nevis	32	54	1	55	0	142
Saint Lucia	32	108	2	57	0	199
Saint Martin	26	85	0	55	0	166
Saint Pierre and Miquelon	25	38	0	0	0	63
Saint Vincent and the Grenadines	35	62	3	57	0	157
Samoa	26	75	0	285	0	386
San Marino	55	129	8	0	0	192
Sao Tome and Principe	34	94	7	10	0	145
Saudi Arabia	82	316	8	330	0	736
Senegal	191	572	36	10	0	809
Serbia	91	264	21	0	0	376
Seychelles	29	74	11	323	1	438
Sierra Leone	210	600	62	10	0	882
Singapore	82	276	27	514	1	900
Sint Maarten	1	79	0	0	0	80
Slovakia	82	221	18	0	0	321
Slovenia	88	229	20	4	0	341
Solomon Islands	78	261	18	510	1	868
Somalia	179	605	32	308	0	1124
South Africa	312	751	126	97	38	1324
South Georgia	28	49	0	0	0	77
South Korea	81	272	19	3	0	375
South Sudan	262	847	42	0	2	1153
Spain	134	350	34	4	0	522
Sri Lanka	115	359	94	304	2	874
Sudan	189	628	24	303	0	1144
Suriname	238	702	109	0	0	1049
Swaziland	146	488	44	0	11	689
Sweden	76	253	12	0	0	341
Switzerland	83	219	18	0	0	320
Syria	99	288	9	4	0	400
Tajikistan	88	307	1	0	0	396
Tanzania	399	1081	200	279	6	1965
Thailand	340	911	155	514	12	1932
The Former Yugoslav Republic of Macedonia	78	241	14	0	0	333
Timor-Leste	67	226	8	568	1	870
Togo	209	593	53	10	1	866
Tokelau	24	39	0	209	0	272
Tonga	27	58	0	222	1	308
Trinidad and Tobago	116	375	35	57	0	583
Tunisia	84	286	6	4	0	380
Turkey	155	359	34	4	0	552
Turkmenistan	99	318	4	0	0	421
Turks and Caicos Islands	30	93	0	55	1	179
Tuvalu	25	45	0	355	0	425
Uganda	355	1010	74	0	4	1443
Ukraine	109	294	19	0	0	422
United Arab Emirates	58	185	2	117	0	362
United Kingdom	73	252	7	3	0	335
United States	452	847	280	302	2	1883
United States Minor Outlying Islands	28	52	0	226	0	306
Uruguay	126	422	47	0	0	595
US Virgin Islands	29	66	4	55	0	154
Uzbekistan	101	325	1	0	0	427
Vanuatu	39	118	0	383	1	541
Vatican City	52	161	10	0	0	223
Venezuela	404	1390	327	63	3	2187
Vietnam	319	814	202	406	24	1765
Wallis and Futuna	25	47	0	310	0	382
Western Sahara	71	188	5	1	0	265
Yemen	84	259	6	341	0	690
Zambia	256	736	93	0	1	1086
Zimbabwe	212	625	65	0	2	904

Limitations and caveats

Because global distribution data are only available for the groups listed above, the results may not reflect trends in extinction risk of other taxonomic groups.
The differing assessment dates require interpolation and extrapolation to estimate aggregate trends.
Red List categories are necessarily broad classes of extinction risk, so the RLI is moderately sensitive.

Where can I get more information about this indicator?

More information and further resources are available in the indicator factsheet here.
SDG Indicator metadata here.

Data sources

International Union for Conservation of Nature (IUCN)
Bird Life International

References

Butchart, S. H. M., Stattersfield, A. J., Bennun, L. A., Shutes, S. M., Akçakaya, H. R., Baillie, J. E. M., Stuart, S.N., Hilton-Taylor, C., Mace, G. M. (2004). Measuring global trends in the status of biodiversity: Red list indices for birds. PLoS Biology, 2(12).

Butchart, S. H. M., Stattersfield, A. J., Baillie, J. E. M., Bennun, L. A., Stuart, S. N., Akcakaya, H. R., Hilton-Taylor, C., Mace, G. M. (2005). Using Red List Indices to measure progress towards the 2010 target and beyond. Philosophical Transactions of the Royal Society B: Biological Sciences, 360(1454), 255-268.

Butchart, S. H. M., Akçakaya, H. R., Chanson, J., Baillie, J. E. M., Collen, B., Quader, S., Turner, W.R., Amin, R., Stuart, S.N., Hilton-Taylor, C. (2007). Improvements to the Red List Index. PLoS ONE, 2(1).

Butchart, S. H. M., Walpole, M., Collen, B., van Strien, A., Scharlemann, J. P. W., Almond, R. E. A., Baillie, J.E.M., Bomhard, B., Brown, C., Bruno, J., Carpenter, K.E., Carr, G.M., Chanson, J., Chenery, A.M., Csirke, J., Davidson, N.C., Dentener, F., Foster, M., Galli, A., Galloway, J.N., Genovesi, P., Gregory, R.D., Hockings, M., Kapos, V., Lamarque, J., Leverington, F., Loh, J., McGeoch, M.A., McRae, L., Minasyan, A., Morcillo, M.H., Oldfield, T.E.E., Pauly, D., Quader, S., Revenga, C., Sauer, J.R., Skolnik, B., Spear, D., Stanwell-Smith, D., Stuart, S.N., Symes, A., Tierney, M., Tyrrell, T.D., Vié, J., Watson, R. (2010). Global biodiversity: Indicators of recent declines. Science, 328(5982), 1164-1168.

Hoffmann, M., Hilton-Taylor, C., Angulo, A., Böhm, M., Brooks, T. M., Butchart, S. H. M. ..., Stuart, S. N. (2010). The impact of conservation on the status of the world's vertebrates. Science, 330(6010), 1503-1509.