Justification of Red List Category
This species has undergone extreme population size fluctuations at major colonies in Chile, but there are considerable uncertainties in the population size and trend. Observed declines in Peruvian colonies and an overall reduction in the number of breeding colonies indicate that there is probably an ongoing, underlying rapid decline in numbers. The species consequently qualifies as Vulnerable. However, if the Chilean population, which comprises the majority of the global population, is found to be stable, the species will warrant downlisting in the future.
A census of the breeding population in Chile carried out in spring 2017, considering all known colonies, suggests that this country holds a population of 5,100 breeding pairs, equating to 10,200 mature individuals. A census of moulting birds, including mature and immature individuals, carried out in January 2017 in Peru, accounted for 13,600 individuals in this country (P. McGill pers. comm.). This roughly equates to a global population of 23,800 mature individuals, though this is considered a maximum value.
A current analysis of the population trend reveals high uncertainty in the quality of population numbers taken in the past three generations, with important deficiencies in the coverage of breeding sites and in the methodology employed to count penguins within and between Peru and Chile (Simeone and Cárdenas unpubl.). Most breeding colonies in Peru declined in numbers between 1980 and 2008 (Vianna et al. 2014). In contrast, some colonies in northern Chile showed a positive trend over the same time period; however, the significant population increase in the largest breeding colony at Chañaral Island was attributed to a considerable underestimation of penguin numbers in the past, and thus likely does not represent a real increase in numbers (Mattern et al. 2004, Vianna et al. 2014). Colonies in central Chile showed a stable or negative trend. As a consequence, interpreting the current trend of the global population is problematic and further research is needed. However, considering the lack of evidence for an overall stability or increase in numbers, the current population trend is precautionarily retained as declining.
Spheniscus humboldti occurs along the coastal zone from Isla Foca (5° 12´S) in Peru down to Isla Guafo (43° 32´S) in southern Chile. At least 49 breeding sites have been confirmed between Punta Aguja (5° 47´S) and Isla Metalqui (42° 12´S) in Peru and Chile, respectively (Reyes-Arriagada et al. 2009). Key colonies are situated at Punta San Juan and Isla Santa Rosa in Peru, and Pan de Azúcar, Chañaral, Choros, Tilgo and Pajaros Island in Chile. A vagrant individual was recorded in Alaska, although it likely was transported by boat (Van Buren and Boersma 2007).
Historically, the population suffered a severe decline starting in the mid-1800s due to the extensive guano harvest in Peru and northern Chile, which removed the preferred nesting habitat (Murphy 1936). According to Johnson (1965), the Humboldt Penguin occurred by the “hundreds of thousands” before the guano exploitation started. In the early 1980s, just prior to the 1982-83 El Niño event, the global population was estimated at 16,000-20,000 birds (Hays 1986, Araya and Todd 1987). After this El Niño event, numbers dropped to 5,000-6,000 individuals, but it is uncertain whether this reduction actually represented mortality or dispersal or a combination of both (Hays 1986, Araya and Todd 1987).
Evidence from satellite-tracked individuals suggests that part of the population migrate between 600-1,000 km northwards during the winter. This has been observed from colonies in northern Chile (Culik and Luna-Jorquera 1997a) and southern Chile (Pütz et al. 2016). Based on band recoveries, Wallace et al. (1999) showed dispersal of penguins from a colony in central Chile up to 600 km to the south and 80 km to the north. Recent geolocation sensor data for Peru indicates post moult movements from breeding individuals at Punta San Juan (15º 22'S) southward up to the Magellan Region (49º 51'S) in Chile (Paredes et al. unpubl. data).
Breeding sites It nests on islands and rocky coastal stretches, using a variety of nest types including guano and dirt burrows, surface nests, vegetation- and rock-covered scrapes, rock crevices, sea caves and under rocks at breakwater walls (Battistini and Paredes 1999, Simeone and Bernal 2000, Paredes and Zavalaga 2001). It apparently prefers to breed on slopes at high elevation sites where guano deposits are available for burrow excavation (Paredes and Zavalaga 2001).
Reproductive behaviour Breeding occurs year-round, but has two peaks, in autumn-winter (April through July) and in spring (August through December), with latitudinal shifts in dates between Peru and Chile (Paredes et al. 2002, Simeone et al. 2002, de la Puente et al. 2013).
Moult Birds moult mainly during January and February, but moult in juveniles is less synchronous (Simeone et al. 2002, Paredes et al. 2003, de la Puente et al. 2013).
Migratory range It is uncertain whether this is a migratory species, but a part of the population migrates after moult (March), with birds from Pan de Azúcar migrating over 600 km (Culik and Luna-Jorquera 1997b) and birds from Puñihuil over 1,000 km (Pütz et al. 2016) northwards from their colonies.
Diet Depending on locality, it feeds on a variety of fish species including Peruvian Anchovy (Engraulis ringens), Araucanian Herring (Strangomera bentincki), Silverside (Odontesthes regia), Common Hake (Merluccius gayi), Inca Scad (Trachurus murphyi), Garfish (Scomberesox saurus scombroides) and South American Pilchard (Sardinops sagax). Diet also includes squid: Dosidiscus gigas and Loligo gahi (Herling et al. 2005).
Foraging behaviour Humboldt Penguins are highly dependent on predictable food resources in coastal waters near the nesting sites (Taylor et al. 2002). During the chick-rearing period, adults forage within 20-35 km around the colony, while incubating birds may reach up to 72 km from the colony (Culik and Luna-Jorquera 1997a, Culik et al. 1998, Chiu et al. 2011). The species typically makes short, shallow dives within 30 m of the surface (Taylor et al. 2002). At Isla Pan de Azúcar, Chile, it was found that maximum dive depth was 53 m.
Population health Health surveys conducted on breeding adults from Punta San Juan showed that birds are in good condition. Haematology, plasma chemistries, and plasma mineral levels varied between years. Positive antibody titers for Chlamydophila psittaci (62%), avian adenovirus (7%), paramyxovirus-2 (7%) and Salmonella pullorum (7%) were found (Smith et al. 2008). Sallaberry-Pincheira et al. (2015) detected Haemoproteus sp. in wild ranging Humboldt Penguins at Punta San Juan, but it is unclear whether Haemoproteus sp. sporozoites are able to infect and develop in penguin cells (see Levin et al. 2013, Valkiunas et al. 2014) and, until this has been conclusively demonstrated, it seems unlikely that these parasites pose a significant threat for their conservation (Vanstreels et al. 2016).
Pollution Humboldt Penguins at Punta San Juan were evaluated for 55 important trace elements, including Hg [maximum Hg concentrations in serum (0.0056 ± 0.001 µg/g), whole blood (0.297 ± 0.0683 µg/g), and feathers (1.8 μg/g dw)], but at levels generally not considered to cause health impairment. Plasma samples from the same animals were analysed for 31 polychlorinated biphenyls (PCB) and 11 organochlorine (OC) residues using gas chromatography coupled to an ion trap mass spectrometer and for 15 polybrominated diphenyl ethers (PBDE) using gas chromatography high-resolution mass spectrometry. The detection rate for PCBs was 69%, with congeners 105, 118, 180, and 153 most commonly detected (Adkesson unpubl. data).
The Humboldt Current System has alternating blooms and depletions of productivity triggered by El Niño-La Niña dynamics. During El Niño, prey availability is reduced to penguins (Culik et al. 2000, Taylor et al. 2002), inducing nest abandonment and chick mortality (Paredes and Zavalaga 1998, Simeone et al. 2002). However, La Niña conditions improve food availability, producing higher breeding success and chick survival (Simeone et al. 2002). Increased frequency and intensity of El Niño events will likely harm the Humboldt Penguin by reducing its ability to recover fast enough, as has been observed in the Galápagos Penguin Spheniscus mendiculus (Boersma 1998, Vargas et al. 2006). Flooding has been recorded to cause species mortality and a loss of reproductive success in some areas of this species’s range.
The high number of artisanal gillnet fisheries operating within the species range is a considerable concern for the species, and may be of greater impact than large-scale fisheries (Crawford et al. 2017). Industrial fisheries in Peru and Chile exploit the main prey species of penguins (sardines and anchovies). A study by Jahncke et al. (2004) demonstrated that the removal of forage fish is an important pressing threat to several seabirds in the Humboldt Current Ecosystem, that may be hindering their ability to recover to pre-industrial fisheries population levels. Gillnets from artisanal fisheries regularly entangle and kill penguins both in Chile (Simeone et al. 1999, Wallace et al. 1999, Skewgar et al. 2009) and Peru (Majluf et al. 2002, J. Alfaro-Shigueto pers. comm.), and penguins have been shown to be caught as bycatch in large-scale trawl, porse-seine and long-line fisheries throughout their range (Crawford et al. 2017). Simeone et al. (1999) suggest that more penguins die in gill nets during winter, when birds are away from the colonies. In Peru, illegal use of explosives by fishermen has caused penguin mortality (J. Reyes pers. comm.); this also occurs in northern Chile, although it seems to be infrequent (CONAF 2016).
Introduced rats (House Rat Rattus rattus and Brown Rat R. norvegicus) predate unattended eggs at several colonies in north and central Chile (Simeone and Luna-Jorquera 2012) and have also been recorded killing chicks in Punta San Juan, Peru (S. Cárdenas-Alayza pers. obs.). Feral dogs Canis familiaris have been reported to kill adults at Pájaro Niño Island in central Chile (Simeone and Bernal 2000) while feral cats Felis catus have been observed on some islands with breeding colonies in Peru. Native Culpeo Lycalopex culpeo have been noted to cause considerable mortality in coastal colonies in Peru, while gulls and vultures are typical egg and chick predators (M. Cardeña pers. comm.).
Disturbance impacts may be locally significant for the species. Penguin colonies are frequently visited by tourists and fishermen collecting seafood or seaweeds in northern Chile (Simeone and Schlatter 1998, Ellenberg et al. 2006, CONAF 2016) and Peru. Simeone and Schlatter (1998) reported considerable trampling of nests by unregulated tourists at Puñihuil Islands and by guano harvesters in Peru (P. Majluf pers. comm.). As the species is extremely sensitive to human presence, breeding success is significantly reduced at frequently visited sites (Ellenberg et al. 2006).
Historical declines resulted from over-exploitation of guano, which greatly reduced the availability and quality of nesting habitat (Coker 1920, Murphy 1936). Removal of guano reduces the preferred substrate used by penguins to dig burrows (Murphy 1936, Duffy et al. 1984, Paredes and Zavalaga 2001), but guano miners also increase adult and egg mortality through direct harvest, trampling of nests, direct disturbance to breeding sites and by the introduction of alien species such as dogs and rats (Duffy et al. 1984). The coastal and marine area around the major colonies in northern Chile (29-30°S) is currently threatened by the construction of coal-fired power stations (Cárcamo et al. 2011) and large mining proposals (E. Vilaplana in litt. 2018). An industrial mega-port has been approved in the bay close to Punta San Juan, the largest colony for Peru (P. Majluf pers. comm.). In northern Chile, eggs are collected for local consumption and birds are killed for use as fish and crab bait.
There is also the potential for oil spills affecting some colonies. In central Chile, two major oil spills occurred in the period 2015-2016, threatening the colony at Cachagua, which contains 800 mature individuals. Over the longer term, the reproductive success of oiled individuals is likely to be impaired and impacts on the marine environment are likely to impact food resources in concert with climate impacts.
Conservation Actions Underway
Colonies in Peru and Chile are monitored regularly. In January 2010, the Peruvian government established the Guano System National Reserve (Decreto Supremo 024–2009-MINAM) (Ministerio de Ambiente 2012, http://www.minam.gob.pe/wp-content/uploads/2013/09/decreto_supremo_024-2009.pdf). This network of headlands, capes and islands harbours nesting sites of Humboldt Penguins and protects major foraging areas around them. The San Fernando National Reserve (established in July 2011 by the Decreto Supremo 017–2011-MINAM) is also a major site for penguins. Monitoring and removal of rodents has recently begun at Punta San Juan (Cárdenas-Alayza unpubl.). Recently, the Chilean Forest Service eradicated rabbits from Isla Choros in northern Chile, and they have developed an Action Plan (CONAF 2016) for the species aiming to improve its conservation in the country and particularly within the protected area network. Currently, the National Zoo in Santiago (Chile) is successfully developing an ex-situ programme by raising chicks from neglected eggs taken from wild populations. Recently, the Shimonoseki Marine Science Museum (Japan) succeeded in artificially inseminating female penguins from frozen sperm (K. Ueda pers. comm.).
Conservation Actions Proposed
Currently, population estimates for Peru and Chile are determined by different methods and this prevents comparisons and estimates of the global population. Therefore, a consolidated census methodology for both Peru and Chile should be established. Determine the optimum survey times and methods for assessing the population size of the species in both countries (e.g. define whether censuses of breeding or moulting birds [or both] should be conducted for the species). Quantify the impact of identified threats on distribution, abundance, and breeding success. Identify and quantify the impacts of climate change on population size, distribution, and breeding success. Determine basic life history parameters at strategic colonies along the species's distribution, including juvenile dispersal and survival, breeding success and population size. Identify critical areas for conservation, both inland (breeding) and at sea (foraging), and monitor strategic colonies to detect changes in abundance and how colonies behave during periods of food abundance and scarcity. Determine whether the fluctuations in numbers observed during El Niño are caused by mortality, dispersion or a combination of both. Generate relevant information for industrial fishery management and policy (define catch quotas and fishery bans based on ecosystem parameters) and monitor targeted prey species. Generate a baseline of health parameters across the species's distribution. Assess whether the current Marine Protected Area (MPA) system effectively protects penguins, and establish further MPAs around strategic colonies to secure feeding grounds of penguins, at least during the breeding season. At colonies where MPAs already exist, enforcement should be coupled with management plans and measurable objectives, so that conservation practitioners can monitor the efficiency of MPAs and adapt to changes as necessary. It is urgent to reduce bycatch in gillnets along the entire distribution of the species. The industrial anchovy fishery is a threat to Humboldt Penguins, so total allowable catches should be set based on trophic and oceanographic models that include ecological parameters and a precautionary approach, reducing fishing pressure during El Niño years. Implement a sustainable guano harvest method in order to minimize disturbance at the breeding colonies and better preserve nesting habitat. Continue eradication of invasive species, particularly rats. Develop educational programmes on fish and seabird conservation for adults and children to better understand economic and conservation trades-offs with human well-being.
65 cm. Medium-sized, black-and-white penguin. Black head with white border extending from eye around ear-coverts and chin, and joining on throat. Blackish-grey upperparts. Whitish underparts with black breast-band extending down flanks to thigh. Fleshy-pink base to bill. Juvenile has wholly dark head (greyer on sides and chin) and lacks breast-band. Similar spp. Magellanic Penguin S. magellanicus has broader white stripe on head and has more than one breast-band.
Text account compilers
Martin, R., Simeone, A., Hermes, C.
Daigre, M., Luna-Jorquera, G., Adkesson, M., Alfaro-Shigueto, J., Amaro, L., Benstead, P., Bernal, M., Boersma, P., Bussalleu, A., Butchart, S., Calvert, R., Capper, D., Cardeña, M., Clay, R.P., Colchao, P., Cárdenas, S., Figueroa, J., Flores, M., Garcia Borboroglu , P., Guillermo, E., Hatchett, J., Jaime, M., Knauf, G., Lascelles, B., Luyo, P., Majluf, P., McGill, P., Moreno, R., Pearmain, L., Quispe, M., Reyes, J., Roca, M., Schneider, T., Simeone, A., Ueda, K., Valqui, T., Vilaplana, E. & Zavalaga, C.
BirdLife International (2021) Species factsheet: Spheniscus humboldti. Downloaded from http://www.birdlife.org on 17/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 17/10/2021.