Africa Wild

5.3 Population Trends
The overall (Namibian and South African) population numbers in the 1920s were probably of the order of millions, with
reports of around one million pairs on Dassen Island alone (Crawford et al. 2007). By 1956/57 numbers decreased to
about 141,000 pairs (Kemper et al. 2007a). It further declined to about 69,000 pairs in 1979/80, c. 63,000 pairs in
2001, c. 57,000 pairs in 2004/05, c. 36,000 pairs in 2006/07 (Kemper et al. 2007a) and c. 25,000 pairs in 2015 (BirdLife
International 2017). The decline in the numbers breeding in South Africa this century is shown in Figure 4.

penguin population.jpg (45.63 KiB) Viewed 1945 times

The decrease of c. 35,000 pairs in African Penguins breeding in South Africa between 2001 and 2009 was investigated
in detail to ascertain the probable causes of mortality (Crawford et al. 2011, Crawford et al. 2017a). The loss of 24,000
pairs (48,000 breeding birds) west of Cape Agulhas was mainly attributable to a decreased abundance of sardine
Sardinops sagax, which led to increased annual mortalities of adult penguins north of Cape Town after 2004 from c.
15% when sardine was plentiful to as much as 50% when it was scarce (Crawford et al. 2011, 2014, Sherley et al.
2014, Robinson et al. 2015). Therefore, except for mortalities due to other known causes, all losses of birds breeding
west of Cape Agulhas were considered to have resulted from food scarcity

6. THREATS
6.1 Food scarcity
Many of the recent population declines of African Penguins have resulted from food shortages caused by shifts in the
distributions of prey species and competition with commercial purse-seine fisheries for food (e.g. Crawford et al. 2011,
2018). There was an eastward shift in the distribution of sardine and anchovy, with the mature biomass of these species
near the breeding islands north of Cape Town decreasing in the early 2000s (Coetzee et al. 2008). The abundance of
these prey species is known to influence breeding success (Crawford et al. 2006a, Sherley et al. 2013), adult survival
(Sherley et al. 2013, Robinson et al. 2015) and juvenile survival (Weller et al. 2016) of African Penguins, all of which
may often be too low off South Africa’s west coast to maintain population equilibrium (Weller et al. 2014, 2016). In
Namibia, where sardine and anchovy are virtually absent from the foraging ranges of breeding penguins, breeding
birds feed predominantly on the energy-poor bearded goby Sufflogobius bibarbatus (Ludynia et al. 2010).
The observed decrease in foraging effort at St Croix Island (Pichegru et al. 2010) and increase in chick survival and
chick condition at Robben Island (Sherley et al. 2015, 2018), which followed the establishment of 20 km no-take zones
around these colonies, demonstrates that it is possible to implement interventions that reduce the threats associated
with resource competition.
In order to ensure sufficient provisioning of food, it will be necessary to preclude fishing of the penguins’ main prey
items around all their important breeding colonies and during the non-breeding season at feeding grounds that are
used for fattening before and after a moult.

6.2 Exploitation and human disturbance
Penguins have in the past been exploited through harvesting of their eggs for food and by the removal of guano for
use as fertiliser. Egg-collecting, now no longer legal, was probably the primary driver of the decrease of the species in
the early 20th century (Frost et al. 1976b, Shannon and Crawford 1999). Guano collection was historically a major
cause of disturbance at many colonies as the removal of guano deprived penguins of nest-burrowing sites. This led to
birds nesting on open ground where they are more vulnerable to heat stress (often resulting in the abandonment of
nests), flooding of nests by rain and predation (Frost et al. 1976b, Shannon and Crawford 1999, Pichegru 2013, Kemper
2015).
African Penguins are regularly injured or killed by entanglement in discarded fishing lines (Crawford et al. 2017). Efforts
to reduce marine litter are clearly called for. African Penguins are occasionally caught in fishing nets and such mortality
is likely to increase if gill-nets are set near colonies (Ellis et al. 1998).
Humans and penguins often come into direct contact at some colonies. Tourists visiting Stony Point and Simon’s Town
colonies frequently interact with African Penguins, and some fail to observe rules, often leaning over or even crossing
barriers to photograph penguins or attempting to touch them. Researchers and management staff at most colonies
also interact with African Penguins to gather necessary data and to implement conservation actions.
The impact of the potential disturbance caused by these penguin-human interactions is not yet fully understood. It is
known that impacts of human disturbance vary widely across species. For example, Humboldt Spheniscus humboldtii
and Yellow-eyed Megadyptes antipodes penguins appear to be particularly sensitive to disturbance (Ellenberg et al.
2006, 2007), while other species, e.g. Gentoo Pygoscelis papua (Holmes et al. 2006), Adélie P. adeliae (Carlini et al.
2007) and Magellanic Penguins S. magellanicus (Villanueva et al. 2012), show no detrimental effects caused by human
presence.
Research that has been carried out on African Penguins suggests that they can and do habituate to regular human
approaches to nests (Pichegru et al. 2016) and beach groups (van Heezik and Seddon 1990) and regular nest visits
(Barham and Sherley 2013). Chicks of birds that are disturbed at erratic intervals appear to show reduced body
condition (Barham and Sherley 2013).

6.3 Catastrophic events
Past mortality from oil spills has been substantial (Wolfaardt et al. 2009b) and may increase if the proposed
development of harbours close to colonies proceeds. Most of the population is confined to areas that are near existing
or planned major shipping routes or ports. There has been a dramatic increase in the number of birds oiled since 1990:
30,000 individuals were oiled in two individual oil spills (in 1994 and 2000). Long-term survival and breeding of these
birds have been impaired despite successful rehabilitation programmes (Underhill et al. 1999, Crawford et al. 2000,
Wolfaardt et al. 2008a, 2009b). For example, breeding success on Robben island fell to 0.23 chicks per pair following
the spill in 2000, compared with an average of 0.62 ± 0.19 over the other 15 years from 1989 to 2004 (Crawford et al.
2006a). Rehabilitation of oiled birds does not necessarily ensure good subsequent reproduction by such birds. During
2001–2005, pairs involving at least one bird rehabilitated from the oil spill in 2000 showed a reduced breeding success
of 0.66 chicks per pair per year compared to 1.02 chicks per pair per year in unaffected pairs. This was largely
attributable to lower fledging success (43%), mostly owing to higher mortality in older chicks, compared to unaffected
pairs (61%) and those involving at least one bird affected by a previous oil spill (71%) (Barham et al. 2007). This may
indicate physiological or behavioural problems that reduce the parents' ability to meet the food requirements of older
chicks, perhaps on account of the toxicity of the heavy oil in the 2000 spill or prolonged captivity and time between
oiling and washing of birds in that spill (Barham et al. 2007).

6.4 Predation
At-sea predation includes that by Cape fur seals Arctocephalus pusillus, which impose significant mortality at some
colonies (Makhado 2009, Makhado et al. 2013, Weller et al. 2016), and sharks (Randall et al. 1988).
Kelp Gulls Larus dominicanus scavenge deserted and unguarded clutches and small chicks especially at surface nests
(Cooper 1974). Culling of Kelp Gulls at Bird Island in Algoa Bay led to improved penguin breeding success (Pichegru
2013).
Feral cats prey on eggs and chicks at some colonies (Weller et al. 2014, 2016). At mainland colonies, predation by
domestic animals (including feral dogs) remains a problem. Predation by natural predators including mongooses,
Leopards Panthera pardus and Caracals Caracal caracal also may severely affect mainland colonies (e.g. Underhill et
al. 2006, Vanstreels et al. unpublished data, CCT, SANParks and CN, unpublished data). Occasional predation of eggs
and small chicks by mole snakes Pseudaspis cana at Robben Island (Dyer 1996) is not considered a major threat at
present.

6.5 Interspecies Competition and Displacement (for food and habitat)
Cape Fur Seals Arctocephalus pusillus pusillus and Cape Gannets Morus capensis compete with African Penguins for
food and habitat at some breeding localities, e.g. Lambert’s Bay and Bird Island in Algoa Bay (Crawford et al. 1989,
David et al. 2003, Kirkman 2009).

6.6 Climate change
It is likely that environmental change has resulted in a mismatch in the distributions of breeding colonies and prey
resources of African Penguins, leading to food scarcity and large decreases in penguin numbers off South Africa’s
west coast (Crawford et al. 2015). It is thought that changes in sea surface temperatures, atmospheric surface pressure
and winds have affected spawning conditions for sardine and anchovy stocks and resulted in a shift in the distribution
of these species towards the east of the Agulhas Bank (Roy et al. 2007; Coetzee et al. 2008). This may have been
exacerbated by intensive fishing of sardine in the west (Coetzee et al. 2008).
In the longer term, climate change may decrease the extent of habitat suitable for the species at the northern extent of
its historical range (BirdLife International 2017). As is the case for Bank Cormorants Phalacrocorax neglectus (Sherley
et al. 2012b), an increase in the frequency and intensity of storms and in ambient temperatures may reduce the
breeding success of birds at low-elevation or unshaded nest sites.
Recent observations from the Simon’s Town and Robben Island colonies suggest that the increase in the frequency of
long periods of high temperatures early in the breeding season may have resulted in an increase in the rate of nest
abandonment.

6.7 Known diseases of African Penguins
There are a number of viruses, bacteria, fungi, protozoa and parasites that are known to causes diseases in African
Penguins – these are summarised in Table 3. While many can be of a serious nature for captive birds (including those
in rehabilitation centres), most of these diseases are not known to hugely compromise the wild population except for
small chicks and otherwise compromised birds. However, the recent outbreak of Avian Influenza (H5N8) is known to
have caused a number of deaths of adult African Penguins in the wild (Khomenko et al. 2018).

7. SOCIO-ECONOMIC ISSUES AND UTILISATION
Simon’s Town (which includes the areas of Boulders, Seaforth, Burgher’s Walk and Windmill Beach), Stony Point and
Robben Island, provide opportunities for the public to observe the species in its natural habitat and have become
popular tourist destinations (e.g. Lewis et al. 2012). The economic benefits of these colonies include income generated
through entrance fees, provision of jobs and associated tourism benefits to the surrounding areas (Lewis et al. 2012).
For example, the colony at Boulders is one of the world’s most-visited penguin colonies with 885 jobs associated with
it (van Zyl and Kinghorn 2018). In 2018, the likely income generation directly associated with this colony over the next
30 years was estimated at approximately ZAR 6.87 billion (van Zyl and Kinghorn 2018). Given that people are able to
see African Penguins at these sites and the present poor conservation status of the species, any expansion of tourism
to other island colonies would need to be carefully considered before implementation. However, it is hoped that a
recovery of South Africa’s penguins would enable growth of this industry and in line with the National Development
Goals.
The scarcity of food for African Penguins makes it likely that the attainment of several of the APBMP’s objectives will
necessitate the effective management of local competition with the purse-seine fishing industry for sardine and
anchovy, through exclusion of fishing in areas that surround South Africa’s important penguin colonies and any
proposed new breeding locality for the species (See Section 5.9). Although such closures would not affect allowable
catches, it has been argued that they would have a cost to the purse-seine fishery (Berg et al. 2016). However, in
addition to the high socio-economic value of penguins and its potential for growth, it should be borne in mind that other
predators of epipelagic forage resources (e.g. gannets, cormorants, seals, cetaceans, predatory fish) also support
marine ecotourism or alternative fisheries and failure to apply an ecosystem approach to fisheries may result in severe
losses in ecosystem services (e.g. Roux et al. 2013, section 5.10 above).

Discussion
323 African penguin numbers have declined steadily over three generations, resulting in a
324 loss of nearly 60% since of 1989, and reached an historic low of ~20,850 pairs in 2019.
325 Our results show that its classification as Endangered as per the IUCN Red List is
326 warranted going forward. This is clear cause for concern for this species. However,
327 African penguins have not declined at the same rate across their range, which is
328 disjunct between Namibia and the Western and Eastern Cape provinces of South
329 Africa. This is for various reasons, including differences in the nature and severity of
330 threats and local population dynamics. It follows, then, that there are different
331 conservation management priorities for each subpopulation.
332
333 The Namibian population has declined slightly over the last three generations, but the
334 rate of decline is insufficient to warrant any Red List classification under the A criterion
335 other than Least Concern. However, the Namibian penguin population had already
336 declined by ~70% prior to the start of our dataset in 1986, coincident with the collapse
337 of the sardine stocks there in the 1970s [8]. This broad scale assessment also masks
338 a worrying decline to 3,600 pairs in 2007 before the subsequent recovery. The low
339 numbers of penguins in Namibia is likely maintained by a scarcity of small pelagic fish
340 [32,33] and the birds’ reliance on lower energy prey [34]. Monitoring of breeding
341 colonies in Namibia is an ongoing priority, with an annual census of breeding pairs the
342 minimum requirement to track trends in this population. A recent outbreak of avian
343 influenza in some colonies in Namibia have shown the vulnerability of this population
344 to stochastic events, the effects of which are exacerbated at low population levels [35].
345 A lack of reliable recent population data curbs the ability of conservation managers to
346 respond to emergent threats and to do assessments.
347
348 The South African population has declined at a much faster rate than the one in
349 Namibia, resulting in a national classification of Endangered and driving the global
350 conservation status. Despite a small population recovery in the late 1990s and first
351 half of the 2000s, driven mostly by increases in the West Coast region, there has
352 subsequently been a crash the mid-2000s onwards to an historical low of ~13,500
353 pairs in 2019. The short-lived population recovery and subsequent crash were
354 associated with a concomitant boom and then decline in sardine and anchovy biomass
355 [36]. The decline also coincided with an eastward displacement in spawning adults of
356 both these fish [37,38] driven by a combination of environmental change and fishing
357 pressure [38,39], which in turn appears to have worsened the availability of prey for
358 seabirds breeding to the north of Cape Town [40]. The South-West Coast region has
359 remained relatively stable at low levels over the last three generations, while the
360 Eastern Cape region has experienced periods of relative stability followed by declines
361 in the early 2000s and the late 2010s. Because the Eastern Cape population has
362 declined at a slower rate than elsewhere in South Africa, the area has become
363 increasingly important in terms of its relative contribution to the national population.
364
365 A lack of available food, predominantly small pelagic fish, is believed to be the main
366 driver for declines in South Africa over the last three generations [11,36,40,41], with
367 sporadic oiling events, habitat destruction, disturbance, and predation also
368 contributing to declines [42–45]. Thus, a key intervention is the identification and
369 protection of key foraging areas. This has been initiated through a 10-year experiment
370 to investigate the effects of fishing closures around penguin breeding colonies, which
371 has shown some benefits to breeding penguins through a decrease in foraging effort
372 and an increase in chick growth and condition [46–48], although this has been
373 contested [49–51]. The initial identification of areas used by penguins during other
374 parts of their life cycle such as pre- and post-moult and during the first few years after
375 fledging has begun [11,52] but further work is required to determine the most
376 appropriate mechanism to protect penguins during these vulnerable periods [11].
377 Additional spatial management of sardine and anchovy fishing effort, currently
378 concentrated on the West Coast, will assist with addressing the mismatch between
379 fish distribution and fishing effort [38,53]. The hand-rearing and release of chicks [54],
380 and the creation of new breeding colonies have also been suggested as additional
381 ways to mitigate the mismatch between penguin breeding colonies and fish distribution
382 [55] and a pilot site is currently being attempted on the southern coast of South Africa.
383
384 In 2013, the South African government put in place a Biodiversity Management Plan
385 for the African penguin [55]. This plan aimed to halt the decline of the species and
386 thereafter achieve a population growth rate that would result in the down listing of the
387 species’ conservation status. While the plan did not achieve its aim, it provides a more
388 coordinated approach to penguin conservation and many key interventions were
389 initiated through the plan. A revised plan is being prepared with fewer, more threatIt is made available under a CC-BY-NC-ND 4.0 International
390 focused actions, and will be implemented from 2020. Our results highlight a rapid,
391 unsustainable decline of almost 10% per year at colonies in the geographic core of
392 the species breeding range (the colonies to the north of Cape Town) and denote a
393 shift to a situation in which colonies at the geographic edge of the species range in the
394 Eastern Cape currently form the stronghold of the African penguin population. Algoa
395 Bay (the location of the Eastern Cape penguin colonies) has been identified as a
396 marine transport hub and potentially as an Aquaculture Development Zone, increasing
397 the risks of oil spills and human disturbance and impact on the ecosystem of the bay.
398 Accordingly, the Eastern Cape colonies should be viewed as a priority for conservation
399 interventions, as should actions that could contribute to retaining viable breeding
400 populations at the formally large colonies in the West Coast region.