Penguins on Parade

From my vantage point on one of the wonky wooden benches furnishing the “Penguin Walk” in Simon’s Town, I look out over the tranquil turquoise waters of beautiful False Bay. I feel the warmth of the African sun as it begins to thaw out the chilly numbness that descended some months ago and release the last of winter’s icy clutches. While a definite coolness can still be felt in the fresh sea breeze, summer is returning to our golden continent. I close my eyes and allow my remaining senses to soak up the atmosphere… it is short-lived! The overpowering smell of penguin guano is the obvious frontrunner in sense-domination. The pungent smell greets you at the gate like an abrupt slap in the face; the tendrils of the stench teasing your gag reflex, making your eyes water and singeing your nose-hairs. Believe it or not, after a few minutes of bemused distraction you will have unwittingly become accustomed to the pong and as such allowed yourself to indulge in the other, more pleasant, sensations.

DSCF5908

Penguin Walk.

DSCF6021

Their distinctive black and white colouring is a form of camouflage, counter-shading, effective when out at sea. The white underside are for predators looking up and the black back for aerial predators.

DSCF5965

Don’t let this become the future of the African penguin.

I gradually become aware of the fact that my surroundings are bustling with activity. A Cape grey mongoose (Galerella pulverulenta) scurries about in between the burrows, spraying sand in an artistic arc as it rootles around for unattended eggs. A Cape fur seal (Arctocephalus pusillus pusillus) can be seen offshore playing with its food as it tosses an octopus high in the air while the deep thrup-thrup of an Oryx chopper is carried across the water as South African navy personnel are turfed into the sea as part of their manoeuvers. And then there are the penguins. The slap of their feet on the wet sand as they make their way down the beach; the profuse sneezing heard emanating from burrows in the coastal thickets, it sounds like a bout of seasonal hay-fever has descended on the colony. A cacophony of braying adults and squeaking chicks rise up and resonate off the walls of the mountainous amphitheatre, this is the Boulders Penguin Colony.

DSCF5725

Mongoose on the hunt – a threat to nesting success.

DSCN5045

Cape fur seal playing with its octopus lunch!

Boulders is a cluster of inlets nestled between the thickets of coastal Strandveld and the temperate waters of False Bay, a mosaic of substrates constituting the boundary where the mountain falls to the sea. Giant granite boulders shelter these tiny coves from the unforgiving south-easter, the prevailing summer wind well known for howling down the slopes of the Kogelberg and channelling across the bay transforming the tranquil, albeit sometimes choppy, waters into a raging “Hurricane Alley”. This moody environment is located in the naval village of Simon’s Town on the eastern shores of the Cape Peninsula, a gnarled finger of land pointing southward into the Atlantic and Indian Oceans, and is home to the charismatic and African penguin (Spheniscus demersus). These birds are the only species of penguin to breed along the coast of Africa and are endemic to the Benguela Current Upwelling System, an ecosystem extending from southern Angola in the north to Algoa Bay in the east (Kemper 2006; Crawford et al. 2007).

DSCF6014

Some of the collective nouns for a group of penguins include “Parade” and “March”… in keeping with the naval surroundings of the Boulders colony.

DSCN5020

The more insulting “Waddle of Penguins” perfectly captures their “hard-done-by” stride, a more energetic version of the bop-bag toy.

DSCF5953

After a year or two baby blues moult and attain their distinctive black and white adult plumage.

DSCF6011

Penguins are often spotted awkwardly taking a leap of faith off the granite boulders.

DSCF6006

The pink glands present above each eye become more pink as their temperature increases. This is due to more blood flowing through them allowing it to be cooled by the surrounding air.

Ranked as Endangered on the IUCN Red List, the global number of these penguins was drastically reduced from approximately 1.5 million in 1910 to as little at 150 000 by the end of the century (Kemper et al. 2007). This alarming decline was driven by the excessive harvesting of eggs and guano resulting in the species very nearly succumbing to extinction. The global population was recorded in 2009 at just over 25 000 breeding pairs located on four mainland and 25 island sites in both Namibia and South Africa (Kemper et al. 2007; Crawford et al. 2011). Seven of these island sites now support 80 % of the global African penguin population with seals having eliminated ten island colonies through predation and competition for shore space (Kemper et al. 2007; Branch et al. 2010). According to the 2012 stats from the Department of Environmental Affairs, 18 683 breeding pairs are what remain along the South African coast.

DSCF6029

Newborn chicks are covered in a down that is not waterproof.

DSCN5066

From the age of approximately 30 days, both parents head out to sea leaving the juveniles alone and often congregating in creches.

DSCF5785

African penguins are social breeders and nest in colonies but are territorial about the area immediately surrounding their nest sites.

DSCF5794

Land-based enemies include mongoose, genet, kelp gull and domestic cats and dogs.

The more recent declines have been as a result of a combination of contributing factors including fluctuations in environmental conditions, reduction in prey biomass introduced through the heavy fishing pressure of commercial fisheries, increased competition for food with Cape fur seals and oil spills; the largest and most destructive being the 1994 and 2000 spills from MV Apollo Sea and MV Treasure (Crawford et al. 2007; Branch et al. 2010; Pichegru et al. 2012). In combination, these two disasters killed 30 000 penguins along our coast and drastically impacted the breeding success of surviving individuals (Crawford et al. 2006). In addition the eastward shift in their pelagic prey species, sardine (Sardinops sagax) and anchovy (Engraulis capensis), and the subsequent disparity in the distributions of prey and penguin breeding localities has been blamed for their latest decline (Crawford et al. 2006; Crawford et al. 2011). The survival and breeding success of the penguins are closely tied to the abundance and availability of these fishes within 20-30 km of their breeding sites (Pichegru et al. 2012).

DSCF6039

Adult collecting vegetative nesting material.

DSCF6043

Historically penguins excavated their nests in layers of guano but after most deposits were depleted through commercial exploitation, they have been forced to use alternate nesting materials and locations.

DSCF6051

Attempting to fit a large stick through the entrance of its nest…

DSCF6054

… doesn’t fit so it becomes a makeshift gate!

DSCF5890

Being unable to fly, penguins construct their nests on the ground.

DSCF5879

Nests range from a shallow scrape in the open to burrows in the sand and vegetation and more recently the supplied artificial igloo-like nests.

DSCF5873

The average clutch size for these penguins is two.

DSCF5764

The Clifton of penguin burrows… a room with a view!

DSCF5733

Tunnels in the vegetation are commonplace at Boulders.

The importance of prey availability in close proximity to breeding sites was emphasised in 2009 when a study (Pichegru et al.) was carried out at St Croix Island, the world’s largest African penguin colony, and Bird Island in Algoa Bay on the East Coast of South Africa. A small no-take zone was created in the waters surrounding St Croix Island by closing an area with a radius of 20 km to purse-seine fishing while allowing the practice to continue in the waters off Bird Island, 50 km away. The foraging behaviour of adults raising chicks was monitored at both sites before and after the closure revealing that within three months, the birds shifted their core foraging area to within the boundaries of protection. Pichegru et al. (2009) suggests that their results give significant credence to the notion that purse-seine fisheries negatively impact penguin foraging behaviour to such a degree that even relatively small no-take zones can be of an advantage to a struggling population.

DSCF5738

The effects of historic guano collection are being mitigated by the installation of small fiberglass igloo-like nests. The pairs move into these artificial nest-sites very soon after the installation.

DSCF5924

Modified feathers trap air when the birds submerge, effectively “wetsuiting” the body.

DSCF5837

When out on a hunt, speeds of up to 20 km/h can be reached.

DSCF5809

An average dive lasts approximately two and a half minutes to a depth of 30 m.

DSCF5806

Dives to a depth of 130 m have been recorded.

The Boulders colony was established in 1982 with just two breeding pairs swelling to approximately 2 200 individuals by 2003. This increase is thought to be attributed to both immigration from nearby Dyer island and the reduction in pelagic trawling throughout False Bay, commercial purse-seine fishing was banned in the bay in the early 1980s (Hutchings 2000; Branch et al. 2010). Penguins are territorial “central-place foragers”, a behaviour where an animal continually returns to a central spot (most likely a nest) between foraging trips, and as such require a nearby food source as well as ample space on the correct terrain on which to nest (Crawford et al. 2011).

DSCF5938

Penguins work to encircle fish, concentrating them into a baitball.

DSCF5937

The enemies of penguins in the ocean include sharks and fur seals with an occasional attack from an orca being recorded.

Although urban in nature and not as isolated from daily anthropogenic influences as island sites; the calm fishing waters and vegetation-protected sandy inlets of Boulders in theory should provide an ideal habitat for these penguins. The opposite however is true as a trend of slowed population growth over the past few years has been observed in this colony. In an attempt to restrict the inland spread of breeding penguins, a fence was erected along the inland boundary of the reserve in 1996 thus physically inhibiting the population growth of a then threatened species (Peterson et al. 2006). While commercial purse-seine netting is banned in False Bay; the target species have a patchy distribution and are highly migratory, moving outside of the protected bay waters and throughout the greater Benguela System. This, in conjunction with the fact that Boulders is located off the main migration route and therefore bypassed by sardine and anchovy heading to and from their Agulhas Bank spawning grounds, results in lower food availability within False Bay. This becomes apparent in the foraging dynamics observed during a 2006 study. The Boulders penguins exhibited a greater foraging effort, travelling further and foraging longer, than their island counterparts from the west coast (Peterson et al. 2006).

DSCF5731

Penguins have very sharp beaks so are best left in peace.

DSCF5838

Approximately 60 days after hatching, some chicks are already in full juvenile plumage.

DSCF5861

African penguins have webbed feet that assist in thermoregulation. When a penguin overheats, the bare patches on its feet act to dissipate the heat.

While the recovery of the African penguin population appears bleak at first glance, substantial conservation and rehabilitation efforts have been carried out and continue to be put into place in an effort to mitigate the negative effects of overfishing and habitat loss. The largest contributor to the safe-guarding of our penguins is the Southern African Foundation for the Conservation of Coastal Birds.  Since its establishment in 1968 SANCCOB has successfully rehabilitated and released more than 90 000 penguins and coastal birds. A staggering statistic in itself but added to the fact that prior to its formation the fate of just about every oiled penguin was death, emphasising the substantial difference that this organisation is making to the preservation of our coastal avifauna (DeNapoli 2011). In an outstanding display of human compassion and dedication, the rehabilitation of 40 000 African penguins in the wake of the catastrophic 2000 MV Treasure oil spill remains the largest animal rescue event in history. Tens of thousands of concerned citizens volunteered over twelve weeks to capture, relocate, rehabilitate and release the affected birds; 91 % of which were successfully returned to the wild. As part of this colossal operation, a pre-emptive evacuation was carried out on Dassen Island to relocate adults in danger of oiling to Algoa Bay. These penguins then swam the
1 200 km return journey, within 21 days, to be greeted by the much improved and cleaner waters of their restored home range (Branch et al. 2010; DeNapoli 2011).

DSCF5758

The down is replaced by a waterproof blue-grey plumage allowing the young penguins to go out to sea.

DSCF5780

The adults take turns to incubate their eggs, hunt and feed their young.

DSCF5755

Old worn feathers are replaced during the annual moult, a period of 21 days, during which the birds are restricted to land and unable to eat.

DSCF5750

African penguins “fatten up” in the days leading up to their moult to sustain them through the starvation period.

The ongoing monitoring of population trends in response to the impacts of fishing pressures and climate change, the establishment of marine protected areas and captive breeding populations, the maintenance of suitable breeding habitat, the elimination of feral cats on the island sites, the provision of artificial nests and the hand-rearing and release of abandoned chicks are some of the other conservation efforts taking place along our coasts (Crawford et al. 2006). If you would like to get involved and make a difference, SANCCOB run internships and volunteer programs tailored to both local and international helpers.

DSCF5817

Penguins are monogamous, having life-long partners.

Explore. Dream. Discover.

If you come across a distressed coastal bird in the greater Cape Town area please contact SANCCOB on 021 557 6155 or after hours on 078 638 3731. You can also contact the SANParks office at Boulders on 021 786 2329.

The TMNP Boulders Penguin Colony is open in both summer and winter (Gate Times).

REFERENCES

BRANCH GM, GRIFFITHS CL, BRANCH ML & BECKLEY LE. 2010. Two Oceans: A Guide to the Marine Life of Southern Africa. Struik Nature: Cape Town.

CRAWFORD RJM, BARHAM PJ, UNDERHILL LG, SHANNON LJ, COETZEE JC, DYER BM, LESHORO TM & UPFOLD L. 2006. The Influence of Food Availability on Breeding Success of African Penguins Spheniscus Demersus at Robben Island, South Africa. Biological Conservation 132(1): 119-125.

CRAWFORD RJM, UNDERHILL LG, UPFOLD L, & DYER BM. 2007. An Altered Carrying Capacity of the Benguela Upwelling Ecosystem for African Penguins (Spheniscus demersus). Journal of Marine Science 64: 570 576.

CRAWFORD RJM, ALTWEGG R, BARHAM BJ, BARHAM PJ, DURANT JM, DYER BM, GELDENHUYS D, MAKHADO AB, PICHEGRU L, RYANPG, UNDERHILL LG UPFOLD L, VISAGIE J, WALLER LJ & WHITTINGTON PA. 2011. Collapse of South Africa’s Penguins in the Early 21st Century. African Journal of Marine Science 33(1): 139-156.

DENAPOLI D. 2011. The Great Penguin Rescue. Simon & Schuster: New York.

HUTCHINGS K. 2000. Catch, Effort and Socio-Economic Characteristics of the Gill and Beach-Seine Net Fisheries in the Western Cape, South Africa. MSc Thesis: University of Cape Town, Cape Town.

KEMPER J. 2006. Heading Towards Extinction? Demography of the African Penguin in Namibia. PhD Thesis: University of Cape Town, Cape Town.

KEMPER J, UNDERHILL LG, CRAWFORD RJM & KIRKMAN SP. 2007. Revision of the Conservation Status of Seabirds and Seals Breeding in the Benguela Ecosystem. In: KIRKMAN SP. (ed.) Final Report of the BCLME (Benguela Current Large Marine Ecosystem).

PETERSEN SL, RYAN PG & GREMILLET D. 2006. Is Food Availability Limiting African Penguins Spheniscus demersus at Boulders? A Comparison of Foraging Effort at Mainland and Island Colonies. Ibis 148: 14-26.

PICHEGRU L, RYAN PG, LE BOHEC C, VAN DER LINGEN CD, NAVARRO R, PETERSEN S, LEWIS S, VAN DER WESTHUIZEN J & GRÉMILLET D. 2009 Overlap Between Vulnerable Top Predators and Fisheries in the Benguela Upwelling System: Implications for Marine Protected Areas. Marine Ecology Progress Series 391: 199-208.

PICHEGRU L, GRÉMILLET D, CRAWFORD RJM & RYAN PG. 2012. Marine No-Take Zone Rapidly Benefits Endangered Penguin. Biology Letters 6(4): 498-501.

South African National Parks: Boulders Penguin Colony Information Leaflet.

6 thoughts on “Penguins on Parade

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s