The conservation status and population decline of the African penguin deconstructed in space and time

AbstractUnderstanding changes in abundance is crucial for conservation, but population growth rates often vary over space and time. We use 40 years of count data (1979–2019) and Bayesian state-space models to assess the African penguin Spheniscus demersus population under IUCN Red List Criterion A. We deconstruct the overall decline in time and space to identify where urgent conservation action is needed. The global African penguin population met the threshold for Endangered with a high probability (97%), having declined by almost 65% since 1989. An historical low of ~17,900 pairs bred in 2019. Annual declines were faster in the South African population (−4.2%, highest posterior density interval, HPDI: −7.8 to −0.6%) than the Namibian one (−0.3%, HPDI: −3.3 to +2.6%), and since 1999 were almost 10% at South African colonies north of Cape Town. Over the 40-year period, the Eastern Cape colonies went from holding ~25% of the total penguin population to ~40% as numbers decreased more rapidly elsewhere. These changes coincided with an altered abundance and availability of the main prey of African penguins. Our results underline the dynamic nature of population declines in space as well as time and highlight which penguin colonies require urgent conservation attention.

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The conservation status and population decline of the African penguin deconstructed in space and time

Ecology and Evolution ◽

10.1002/ece3.6554 ◽

2020 ◽

Vol 10 (15) ◽

pp. 8506-8516

Author(s):

Richard B. Sherley ◽

Robert J. M. Crawford ◽

Andrew D. Blocq ◽

Bruce M. Dyer ◽

Deon Geldenhuys ◽

...

Keyword(s):

Conservation Status ◽

Population Decline ◽

Space And Time ◽

African Penguin

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Global extinction risk for seahorses, pipefishes and their near relatives (Syngnathiformes)

Oryx ◽

10.1017/s0030605320000782 ◽

2021 ◽

pp. 1-10

Author(s):

Riley A. Pollom ◽

Gina M. Ralph ◽

Caroline M. Pollock ◽

Amanda C.J. Vincent

Keyword(s):

Threatened Species ◽

Habitat Degradation ◽

Extinction Risk ◽

Conservation Status ◽

Field Research ◽

Selective Extraction ◽

Iucn Red List ◽

Point Estimate ◽

Conservation Action ◽

Data Deficient

Abstract Few marine taxa have been comprehensively assessed for their conservation status, despite heavy pressures from fishing, habitat degradation and climate change. Here we report on the first global assessment of extinction risk for 300 species of syngnathiform fishes known as of 2017, using the IUCN Red List criteria. This order of bony teleosts is dominated by seahorses, pipefishes and seadragons (family Syngnathidae). It also includes trumpetfishes (Aulostomidae), shrimpfishes (Centriscidae), cornetfishes (Fistulariidae) and ghost pipefishes (Solenostomidae). At least 6% are threatened, but data suggest a mid-point estimate of 7.9% and an upper bound of 38%. Most of the threatened species are seahorses (Hippocampus spp.: 14/42 species, with an additional 17 that are Data Deficient) or freshwater pipefishes of the genus Microphis (2/18 species, with seven additional that are Data Deficient). Two species are Near Threatened. Nearly one-third of syngnathiformes (97 species) are Data Deficient and could potentially be threatened, requiring further field research and evaluation. Most species (61%) were, however, evaluated as Least Concern. Primary threats to syngnathids are (1) overexploitation, primarily by non-selective fisheries, for which most assessments were determined by criterion A (Hippocampus) and/or (2) habitat loss and degradation, for which assessments were determined by criterion B (Microphis and some Hippocampus). Threatened species occurred in most regions but more are found in East and South-east Asia and in South African estuaries. Vital conservation action for syngnathids, including constraining fisheries, particularly non-selective extraction, and habitat protection and rehabilitation, will benefit many other aquatic species.

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Conservation Status of Marine Biodiversity in Oceania: An Analysis of Marine Species on the IUCN Red List of Threatened Species

Journal of Marine Biology ◽

10.1155/2011/247030 ◽

2011 ◽

Vol 2011 ◽

pp. 1-14 ◽

Cited By ~ 5

Author(s):

Beth A. Polidoro ◽

Cristiane T. Elfes ◽

Jonnell C. Sanciangco ◽

Helen Pippard ◽

Kent E. Carpenter

Keyword(s):

Threatened Species ◽

Environmental Changes ◽

Extinction Risk ◽

Conservation Status ◽

Marine Species ◽

Iucn Red List ◽

Red List ◽

Marine Biodiversity ◽

Conservation Priorities ◽

Conservation Action

Given the economic and cultural dependence on the marine environment in Oceania and a rapidly expanding human population, many marine species populations are in decline and may be vulnerable to extinction from a number of local and regional threats. IUCN Red List assessments, a widely used system for quantifying threats to species and assessing species extinction risk, have been completed for 1190 marine species in Oceania to date, including all known species of corals, mangroves, seagrasses, sea snakes, marine mammals, sea birds, sea turtles, sharks, and rays present in Oceania, plus all species in five important perciform fish groups. Many of the species in these groups are threatened by the modification or destruction of coastal habitats, overfishing from direct or indirect exploitation, pollution, and other ecological or environmental changes associated with climate change. Spatial analyses of threatened species highlight priority areas for both site- and species-specific conservation action. Although increased knowledge and use of newly available IUCN Red List assessments for marine species can greatly improve conservation priorities for marine species in Oceania, many important fish groups are still in urgent need of assessment.

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A globally threatened shark, Carcharias taurus, shows no population decline in South Africa

Scientific Reports ◽

10.1038/s41598-020-75044-2 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Juliana D. Klein ◽

Aletta E. Bester-van der Merwe ◽

Matthew L. Dicken ◽

Arsalan Emami-Khoyi ◽

Kolobe L. Mmonwa ◽

...

Keyword(s):

South Africa ◽

Census Data ◽

Demographic History ◽

Conservation Status ◽

Population Decline ◽

Multilocus Genotype ◽

Population Declines ◽

Effective Population ◽

Anthropogenic Pressures ◽

Carcharias Taurus

Abstract Knowledge about the demographic histories of natural populations helps to evaluate their conservation status, and potential impacts of natural and anthropogenic pressures. In particular, estimates of effective population size obtained through molecular data can provide useful information to guide management decisions for vulnerable populations. The spotted ragged-tooth shark, Carcharias taurus (also known as the sandtiger or grey nurse shark), is widely distributed in warm-temperate and subtropical waters, but has suffered severe population declines across much of its range as a result of overexploitation. Here, we used multilocus genotype data to investigate the demographic history of the South African C. taurus population. Using approximate Bayesian computation and likelihood-based importance sampling, we found that the population underwent a historical range expansion that may have been linked to climatic changes during the late Pleistocene. There was no evidence for a recent anthropogenic decline. Together with census data suggesting a stable population, these results support the idea that fishing pressure and other threats have so far not been detrimental to the local C. taurus population. The results reported here indicate that South Africa could possibly harbour the last remaining, relatively pristine population of this widespread but vulnerable top predator.

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The conservation status of West Indian palms (Arecaceae)

Oryx ◽

10.1017/s0030605307000404 ◽

2007 ◽

Vol 41 (3) ◽

pp. 300-305 ◽

Cited By ~ 13

Author(s):

Scott Zona ◽

Raúl Verdecia ◽

Angela Leiva Sánchez ◽

Carl E. Lewis ◽

Mike Maunder

Keyword(s):

Conservation Status ◽

West Indian ◽

Field Studies ◽

Iucn Red List ◽

Critically Endangered ◽

Ex Situ ◽

Conservation Action ◽

Iucn Red List Categories ◽

Conservation Projects ◽

Data Deficient

AbstractThe conservation status of 134 species, subspecies and varieties of West Indian palms (Arecaceae) is assessed and reviewed, based on field studies and current literature. We find that 90% of the palm taxa of the West Indies are endemic. Using the IUCN Red List categories one species is categorized as Extinct, 11 taxa as Critically Endangered, 19 as Endangered, and 21 as Vulnerable. Fifty-seven taxa are classified as Least Concern. Twenty-five taxa are Data Deficient, an indication that additional field studies are urgently needed. The 11 Critically Endangered taxa warrant immediate conservation action; some are currently the subject of ex situ and in situ conservation projects in the region’s botanical gardens. We recommend that preliminary conservation assessments be made of the 25 Data Deficient taxa so that conservation measures can be implemented for those facing imminent threats.

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A broadly distributed species instead of an insular endemic? A new find of the poorly known Hainan gymnure (Mammalia, Lipotyphla)

ZooKeys ◽

10.3897/zookeys.795.28218 ◽

2018 ◽

Vol 795 ◽

pp. 77-81 ◽

Cited By ~ 1

Author(s):

Alexei V. Abramov ◽

Anna A. Bannikova ◽

Vladimir S. Lebedev ◽

Viatcheslav V. Rozhnov

Keyword(s):

Conservation Status ◽

Natural Habitat ◽

Population Decline ◽

Hainan Island ◽

First Record ◽

Iucn Red List ◽

Biodiversity Survey ◽

Northern Vietnam ◽

The Family ◽

Insular Endemic

The Hainan gymnure Neohylomyshainanensis (Mammalia, Lipotyphla), endemic to Hainan Island (China), is one of the rarest and least-known species within the family Galericidae. The IUCN Red List inferred it as an endangered species due to ongoing population decline caused by natural habitat loss. A recent biodiversity survey has revealed N.hainanensis to be rather common in northern Vietnam. This is the first record of the species outside Hainan Island. New data have allowed us to re-assess the conservation status of this poorly known mammal. The occurrence of N.hainanensis in mainland Vietnam also supports the hypothesis that Hainan Island could have been previously connected to Guangxi and northern Vietnam rather than to neighbouring Guangdong.

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Yellow-naped AmazonAmazona auropalliatapopulations are markedly low and rapidly declining in Costa Rica and Nicaragua

Bird Conservation International ◽

10.1017/s0959270918000114 ◽

2018 ◽

Vol 29 (2) ◽

pp. 291-307 ◽

Cited By ~ 3

Author(s):

TIMOTHY F. WRIGHT ◽

THOMAS C. LEWIS ◽

MARTÍN LEZAMA-LÓPEZ ◽

GRACE SMITH-VIDAURRE ◽

CHRISTINE R. DAHLIN

Keyword(s):

Costa Rica ◽

Species Conservation ◽

Iucn Red List ◽

Allee Effects ◽

Population Declines ◽

Conservation Action ◽

Pet Trade ◽

Comprehensive Survey ◽

Similar Survey ◽

Reproductive Rates

SummaryAccurate assessments of population sizes and trends are fundamental for effective species conservation, particularly for social and long-lived species in which low reproductive rates, aging demographic structure and Allee effects could interact to drive rapid population declines. In the parrots (Order Psittaciformes) these life history characteristics have combined with habitat loss and capture for the pet trade to lead to widespread endangerment, with over 40% of species classified under some level of threat. Here we report the results of a population survey of one such species, the Yellow-naped Amazon,Amazona auropalliata, that is classified as ‘Endangered’ on the IUCN Red List. We conducted a comprehensive survey in June and July of 2016 of 44 night roosts of the populations in contiguous Pacific lowlands of northern Costa Rica and southern Nicaragua and compared numbers in Costa Rica to those found in a similar survey conducted in June 2005. In 2016 we counted 990 birds across 25 sites surveyed in Costa Rica and 692 birds across 19 sites surveyed in Nicaragua for a total population estimate of only 1,682 birds. Comparisons of 13 sites surveyed in both 2005 and 2016 in Costa Rica showed a strong and statistically significant decline in population numbers over the 11-year period. Assessment of group sizes approaching or leaving roosts indicated that less than 25% of groups consisted of three or more birds; there was a significantly higher proportion of these putative family groups observed in Nicaragua than Costa Rica. Taken together, these results are cause for substantial concern for the health of this species in a region that has previously been considered its stronghold, and suggest that stronger conservation action should be undertaken to protect remaining populations from capture for the pet trade and loss of key habitat.

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The Chestnut-banded Plover is an overlooked globally Near Threatened Species

Bird Conservation International ◽

10.1017/s0959270907000779 ◽

2007 ◽

Vol 17 (3) ◽

pp. 283-293 ◽

Cited By ~ 1

Author(s):

Rob Simmons ◽

Neil Baker ◽

Rod Braby ◽

Tim Dodman ◽

Oliver Nasirwa ◽

...

Keyword(s):

East Africa ◽

Conservation Status ◽

Iucn Red List ◽

World Population ◽

Population Declines ◽

Water Abstraction ◽

Arid Habitat ◽

Suitable Habitats ◽

Iucn Red List Criteria ◽

Near Threatened

AbstractSpecies that show obvious population declines are relatively easy to categorize as globally threatened under IUCN Red List criteria. However, species whose populations are highly concentrated at a few inaccessible sites that are unprotected or habitat-threatened and then disperse are more difficult to pigeon-hole. Here we re-assess the conservation status of one such species – the Chestnut-banded Plover Charadrius pallidus – that occurs across Africa in specialized, inaccessible and arid habitat. Wetland bird counts from 1991 to the present allow us to determine a new world population estimate of about 17,830 birds. This allows us to determine a new 1% level and we identified only eight sites in southern and East Africa where these plovers congregate in numbers >1% when non-breeding. There are only five other sites that hold more than 100 birds, indicating that the species is not simply widely dispersed across suitable habitats. Simultaneous counts across southern and East Africa indicate that just three sites – Walvis Bay and Sandwich Harbour in Namibia and Lake Natron in Tanzania – can hold 87% of the world population during non-breeding periods. Since two of these sites are under threat from pollution, siltation and water abstraction, and the eight sites in total comprise just 30% of the area criteria set by IUCN, the bird meets one of the two qualifiers for globally Vulnerable status. Despite this, we cannot detect any long-term declines in population size, partly because of wide variations in population numbers over decadal time periods (itself an IUCN qualifier). It is clear that this bird should move from its present Least Concern status to Near Threatened and conservation measures be enacted at two of the top three sites – Walvis Bay and Lake Natron.

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Conservation status of the Endangered Nubian dragon tree Dracaena ombet in Gebel Elba National Park, Egypt

Oryx ◽

10.1017/s0030605313001385 ◽

2014 ◽

Vol 49 (4) ◽

pp. 704-709 ◽

Cited By ~ 9

Author(s):

M. Kamel ◽

U. M. Ghazaly ◽

M. W. Callmander

Keyword(s):

Global Positioning System ◽

National Park ◽

Action Plan ◽

Conservation Status ◽

Iucn Red List ◽

Population Status ◽

Conservation Action ◽

Global Positioning ◽

Dracaena Ombet ◽

Conservation Action Plan

AbstractThe Nubian dragon tree Dracaena ombet, which is categorized as Endangered on the IUCN Red List, is found on the highest slopes of Gebel Elba National Park in Egypt, with scattered populations in Sudan, Djibouti, Ethiopia and Somalia. The Gebel Elba population is threatened by drought. Surveys were conducted in the Park to assess the condition and document the distribution of the species to prepare a baseline for conservation efforts. Eight sites were surveyed during 2007–2009: trees were tagged and their locations were recorded using a global positioning system, and tree density, diameter at breast height and population status were estimated. Of 353 trees recorded only 46% (161 individuals) were alive and only 27% (96 individuals) were in a healthy condition. Only 1% (2 individuals) were young trees, indicating a low regeneration level. Field-based observations suggest that 80% of the D. ombet population in Gebel Elba may soon be extinct. A conservation action plan is needed for this flagship species in Egypt and throughout its range.

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Rapid population declines of Himalayan Griffon Gyps himalayensis in Upper Mustang, Nepal

Bird Conservation International ◽

10.1017/s0959270908007417 ◽

2009 ◽

Vol 19 (1) ◽

pp. 99-107 ◽

Cited By ~ 10

Author(s):

RAJU ACHARYA ◽

RICHARD CUTHBERT ◽

HEM SAGAR BARAL ◽

KARAN BAHADUR SHAH

Keyword(s):

South Asia ◽

Conservation Status ◽

Population Decline ◽

Population Trends ◽

Himalayan Region ◽

Veterinary Drug ◽

Mountainous Region ◽

Population Declines ◽

Breeding Area ◽

Population Collapse

SummaryThe population collapse of resident Gyps vulture species in South Asia, caused by the use of a veterinary drug diclofenac, has highlighted an urgent need to monitor numbers of other vulture species in the region. This study assessed population trends of Himalayan Griffon Gyps himalayensis in the mountainous region of Upper Mustang, Nepal, which is an important breeding area for the species. Vultures were surveyed in 2002, 2004 and 2005 by recording the number of birds sighted along 188 km of transects, and observing numbers of birds at breeding colonies. The number of birds recorded per day and per kilometre of transect declined by 67% and 70% respectively over the period of study. The number of active nests declined by 84% from 2002 to 2005. The veterinary drug diclofenac was available in pharmacies in the Mustang region. Young Himalayan Griffons, which migrate to the lowland areas of Nepal and, in increasing numbers to India, are highly likely to be subject to diclofenac poisoning. If this rate of population decline occurs throughout the Himalayan region, the conservation status of the species will need to be urgently reassessed.

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