Bad at Goodbyes

Rough Transcript

Intro 00:05

Welcome to Bad at Goodbyes.

On today’s show we consider the Arrayán.

Species Information 02:05

The Arrayán is a critically endangered flowering tree native to South America, specifically the coastal fog oases of the Atiquipa District in southwestern Peru. Its scientific name is Myrcianthes ferreyrae and it was first described in 1958.

 

A member of the Myrtle family, the Arrayán is a small evergreen tree that grows roughly 15-25 feet in height. It has brown-grey-ish bark, and many of its structures (so like branchlets, leaf stems, new buds) grow a dense layer of short, stiff hairs. An adaptation which provides additional surface area for water capture in their arid habitat.

 

Their deep green leaves are thick and leathery, roughly one inch long and a half inch wide. Shaped as both ovate (that’s egg shape, with narrower end at the leaf tip) and as obovate (egg shaped but with the narrower end connected to the leaf stem). The leaf margins, that’s the edges, are thickened and revolute, meaning they curl downward slightly.

 

The Arrayán grows inflorescences, flower clusters of usually three, white four-petaled flowers. The flowers open wide, like lay flat on their receptacle (that’s the base of the flower). And they have very numerous, as many as 50 per flower, long stringy stamen (that’s the male pollen producing organ). The stamen’s filament, that’s the thin stalk is white to almost translucent and the anther (that’s the pollen holder at the tip) is a tiny round yellow dot. The pistil (the female reproductive organ) is similarly colored, the ovary and the style are white and the (pollen-receiving) stigma at the tip is yellow-ish. The flowers look like tiny soft explosions, a white and yellow firework.

 

The Arrayán is hermaphroditic, meaning a single flower has both female and male sex organs. It blooms from late December through late February, in what is called a continuous or steady-state flowering, meaning that plant consistently buds and opens a small number of flowers each day, throughout the flowering season. Contrast that to like a superbloom when everything flowers once and wilts soon after. Here the Arrayán spreads its floral resources over a two month period, opening just a few flowers each day.

 

I could find no direct observation of the tree’s pollinators but given its nectar-production and open flower form, it is likely that the Arrayán is pollinated by bees and butterflies, maybe flies and wasps.

 

And then upon successful fertilization, the flowers produce a small round, berry-like fruit, that is about a quarter-inch in diameter and a dark purple or black when ripe. Each fruit holds one or two seeds.

 

Again, we don’t have solid research on seed dispersal, though again we can infer based on the berry-like fruit that their seeds are likely distributed by zoochory, um, animals. Most likely birds, and possibly mammals consuming the fruit and dispersing the tree’s seeds.

 

The Arrayán’s seeds are recalcitrant meaning they are only viable for a brief amount of time and do not tolerate particularly cold or particularly dry conditions. We will go a little deeper on this later in the show, but simply low natural regeneration is among the threats facing this tree.

 

The Arrayán is native to Peru, in South America, specifically the lomas, these are coastal fog oases in the southwest of the country. The Arrayán is found in six distinct subpopulations, in the Arequipa Department, in the Atiquipa District, about 300 miles south of Lima, right on the Pacific Coast.

 

These lomas are a remarkable and unique ecosystem formed from the confluence of ocean currents, air currents and the coastal landscape, where the foothills of the Andes mountains meet the sea. This is an unbelievably dry region, seeing less than a tenth of an inch of annual rainfall. It is considered a cool desert climate, with mild temperatures year round, ranging from the mids 50s°F to the low 70s.

 

The lomas are these green oases, oases, that’s plural for oasis, forming in this barren and hyperarid environment. Found from about sea level to roughly a half mile up in elevation, on western slopes facing the sea. These pockets of vegetation are only possible because of fog.

 

Okay, time for some meteorology:

So out in the ocean, the Humboldt Current brings very cold water from the south, originating in the sub-antarctic waters off the tip of Chile and moving northward along the western South American coast. As this very cold water meets with the warmer maritime tropical air mass off the Peruvian coast it causes that air to cool, and when the air cools to its dew point, water vapor within condenses into a cloud. In this case, low lying stratocumulus clouds. Low lying because the warmer air above this colder ocean surface air acts as kind of a ‘lid’ preventing the clouds from growing vertically. This is important because when these low clouds come ashore they are blocked by the Andes mountains to the east, held in place by the warm air above, and present, like to those of us on land, as a dense fog. Locals call it, garúa.

 

So due to these climate phenomena, the lomas, these hillside fog oases, are regularly blanketed, from roughly July to November, in dense moist air.

 

As this dense moist air moves through the hillsides, plant life like the Arrayán, the physical structure of the tree itself, its leaves, hairs, branches, trunk, serve as a natural fog collector. Water droplets condense on these surfaces which drip from the canopy and run down the trunk channeling water directly into the soil beneath the tree. This creates a microclimate, a localized zone of collected moisture that sustains the Arrayán, and allows for the establishment of a diverse understory of herbs, brush, and grasses that could not otherwise survive in this desert region. The lifecycles of this understory vegetation in turn provide soil nutrients to the Arrayán. And of course, the vegetation also supports a diversity of animal life. Including indigenous humans, archeologists have found remnants of Incan structures in and near the lomas, suggesting that people too, have historically relied on its specific fog capture and resultant greenery for sustenance in this desert environment.

 

The Arrayán shares its lomas habitat with:

Forest Papaya, Slender-Billed Finch, Atiquipa Scorpion, Tara Tree, Atiquipa Jaltomata, White-Tailed Deer, Pygmy Cactus, Rufous-Collared Sparrow, Northern House Wren, Short-Tailed Field Tyrant, Fiddlewood, Mountain Papaya, Colpeo Fox, Blackish Oystercatcher, Wild Guinea Pig, Long-Spine Acacia, Guanaco, Turkey Vulture, Andean Lapwing, Peruvian Mouse, Vermilion Flycatcher, and many many more.

————

In the dream,

 

In drought, a longing. In the dream an anticipation of the soft sweet lifegiving fog

And then to bathe in it. To sip the cloud soak, to drink from the sky, to wet my dry lips in the gray blanketing air.

 

And to hold it, and to give it.

To tune my self, my body, my instrument to the song cycle of wind and water,

to know my place, to hit my cues, to sing my notes full throated,

A rich harmony

in the grand chorus of living things.

 

In the dream.

————

Historically the population of the Arrayán has been reduced by anthropogenic (that’s human-caused) habitat destruction, fragmentation, and direct collection.

 

Evidence suggests the lomas were once significantly more widespread, up and down the Peruvian coast; today reduced to less than 100 discrete locations, in which the Arrayán is only found in six. Human settlements and infrastructure expansion like roads and dams have destroyed and fragmented the habitat, and historically the tree was harvested as timber for firewood and for building construction.

 

There is some evidence that occasional (now illegal) harvesting continues today.

 

Additionally human introduced domesticated grazers are both an historic and contemporary threat. Overgrazing by cattle, goats and horses affects Arrayán seedlings, they are consumed and/or trampled, and diminishes the understory growth which adult trees rely on.

 

Some research suggests that this shrinking and fragmenting habitat is affecting the Arrayán’s pollinators, that there may not be ample pollinating species to ensure strong reproduction.

 

Successful regeneration was like always precarious, given its recalcitrant seeds and reliance on specialized climate conditions.

 

And so, of course, human induced climate change is a substantial immediate threat. As our world warms, due to persistent human over-reliance on fossil fuel, global weather patterns are shifting. And the Arrayán’s lomas habitat is only possible due to these very particular air and water current patterns. Global warming threatens to disrupt those cycles.

 

Fortunately the Arrayán and the Peruvian lomas in general are seeing conservation activity. The tree is legally protected nationally and internationally. 

 

In 2011, the Peruvian Ministry of the Environment established the Lomas de Atiquipa ACP, a private conservation area, that protects a portion of the Arrayán’s population. Interestingly, what “private” means in this arrangement is that the site is managed by the local rural community that lives within and depends upon the lomas ecosystem, an effort to align the long-term ecological health of the lomas with the economic well-being of its residents. It is a cool model, I’m interested to learn more about and better understand.

 

In the past roughly 20 years, offsite cultivation and re-introduction programs have proven fairly unsuccessful, in part due to the sensitivity of the species’ seeds, making seedbanking impossible and cultivation challenging. A 2010s reintroduction program was thwarted when fences installed to protect from herbivores were breached, the grazers managed to get through and injure the new growth.

 

Recently though, research in 2023 on micropropagation of the tree looks promising. This is an innovative process in which a plant tissue culture is used to grow a large number of new plants from a tiny amount of source material. Scientists took extremely small cuttings of the Arrayán and were able to successfully cultivate multiple viable individuals. That work, as well as continued research into onsite indigenous cultivation practices is ongoing.

 

Nevertheless the Arrayán has been considered critically endangered on the IUCN Red List since 2014 and their population is currently in decline.

 

Our most recent counts estimate that less than 586 Arrayán remain in the wild.

Citations 26:40

Information for today’s show on the Arrayán was compiled from:

 

Botanic Gardens Conservation International. Feb 2025. Gonzales Guillen, Fiorella. “Relict Forest in Fog Oases in South America”.  – https://www.bgci.org/news-events/spotlight-on-a-gtsg-member-project-relict-forest-in-fog-oases-in-south-america/ 

 

Field Museum Of Natural History Botanical Series Vol. 13, Part 4, No. 2. Pg 756. 1958. Mcvaugh, Rogers. “Flora Of Peru”. – https://archive.org/embed/floraofperufimcva

 

The IUCN Red List of Threatened Species 2014: e.T60492231A60492909. Gonzales, F. 2014. “Myrcianthes ferreyrae.” – https://dx.doi.org/10.2305/IUCN.UK.2014-3.RLTS.T60492231A60492909.en

 

Missouri Botanical Garden – https://mbgecologicalrestoration.wordpress.com/tag/lomas-de-atiquipa/

 

PLoS One. Vol. 6, no. 8. 2011:e23004. Balaguer L, Arroyo-García R, Jiménez P, et al. “Forest restoration in a fog oasis: evidence indicates need for cultural awareness in constructing the reference”. – https://doi.org/10.1371/journal.pone.0023004 

 

Proceedings of the 7th Brazilian Technology Symposium. Araujo, Ana & Medina, Fiorella & Flores, Patricia & Lazo, Herbert Omar. (2023). “Micropropagation of Myrcianthes Ferreyrae (McVaugh) “Arrayán”: an Endemic Species from Lomas De Atiquipa.” – http://dx.doi.org/10.1007/978-3-031-04435-9_50

 

Revista Peruana de Biología. Vol. 26, No. 2. 2019. Gonzales Guillén, Fiorella, Villasante Benavides, Francisco. “Estado de conservación de Myrcianthes ferreyrae un árbol endémico de las lomas costeras del sur del Perú”. – http://dx.doi.org/10.15381/rpb.v26i2.16380

 

Tree Physiology, Volume 32, Issue 1, January 2012, Pages 65–73. David A. Ramírez, Luis Balaguer, Rosa Mancilla, Virginia González, Daniel Coaguila, Carmelo Talavera, Luis Villegas, Aldo Ortega, Percy Jiménez, José M. Moreno, “Leaf-trait responses to irrigation of the endemic fog-oasis tree Myrcianthes ferreyrae: can a fog specialist benefit from regular watering?”. – https://doi.org/10.1093/treephys/tpr121

 

UNESCO World Heritage Convention – https://whc.unesco.org/en/tentativelists/6424/

 

For more information about Arrayan and lomas fog oases conservation please see Huarango Nature Peru at  https://www.huarangonature.org and Sociedad Peruana de Derecho Ambiental (SPDA Peru) at https://spda.org.pe 

Music 28:36

Pledge 35:31

I honor the lifeforce of the Arrayán. I will commit its name to my record. I am grateful to have shared time on our planet with this being. I lament the ways in which I and my species have harmed and diminished this species. I grieve.

 

And so, in the name of the Arrayán I pledge to reduce my consumption. And my carbon footprint. And curb my wastefulness. I pledge to acknowledge and attempt to address the costs of my actions and inactions. And I pledge to resist the harm of plant and animal kin and their habitat, by individuals, corporations, and governments.

 

I forever pledge my song to the witness and memory of all life, to a broad celebration of biodiversity, and to the total liberation of all beings.