Batman and other wild nights

Creatures of the night

It’s 5 o’clock in the morning, and the night is waning on our estates.

At Domaine d’Aussières, in the Corbières, a wild boar is gorging itself on bunches of Mourvèdre grapes.

At Château Paradis Casseuil, a goat cuts through two rows of vines along the banks of the Garonne.

At Viña Los Vascos, in the Chilean Colchagua Valley, a lizard takes advantage of a hazy moon to emerge from its hiding place and stretch out on a stone that has finally cooled. 

These scenes, observed on rare occasions by our winegrowers when they are tending to the vines or starting the harvest before daybreak, attest to the richness of our ecosystems. Our nocturnal wildlife presents both threats and opportunities for our vines and wines.

Batman and the butterflies

Jean-Charles Forge, Vineyard Manager at Domaine d’Aussières, recalls a memorable night in July 2021 with “Batman”, the affectionate nickname his team have given to the bat expert tasked with identifying the colonies residing within the estate.

Like two officers monitoring speeding vehicles along a rural road on a summer evening, Jean-Charles and Batman, equipped with an ultrasound instrument, observed the bats throughout the night as they came and went.

An incessant ballet: while some of them hunted with their bare hands (don’t ever call them ‘wings’ when you’re around Batman), others stayed behind to nurse their newborns.

That night of bat watching permitted Jean-Charles and the team to acquire valuable knowledge. Approximately twenty nesting boxes were built and strategically positioned to facilitate the bats’ resting during their nocturnal hunting.

Why such care? Since collaborative research conducted by the Institut National de la Recherche Agronomique (INRA) and the Centre National de la Recherche Scientifique (CNRS) in 2013, it has been shown that bats feed on vineyard pests. DNA remnants from lobesia botrana, a caterpillar that consumes grape pulp, were detected in their excrement. The juice expelled by the insect’s punctures, trapped in the bunches of grapes, induces fungal growth, a rot that haunts the nightmares of every winegrower.

A little later in the season, towards the end of July, lobesia botrana is joined by its even more voracious cousin, cryptoblabes gnidiella. It can destroy a whole bunch of grapes, including the stem.

Despite the abundance and utility of our bats, they are insufficient against these pests. We also counteract them by using a biological pesticide, namely the bacteria bacillus thuringiensis.

Not only is bacillus thuringiensis the caterpillars’ favourite, making it the most lethal, but it also has the benefit of not killing other insects that are helpful to vines. The process has now been perfected. On 22nd and 23rd August 2024, the entire vineyard team at Domaine d’Aussières started work at 2 a.m.. They sprayed a bacillus thuringiensis solution. The bats expressed their gratitude, as did our grapes; they would see the harvest safeguarded from the fluttering wings of satisfied butterflies.

Wild nights

In the Entre-deux-Mers region, at Château Paradis Casseuil, we watch the murmurations of starlings carefully. They have a distinctive sense of taste. When the grapes ripen, the starlings descend on them in large flocks. This means that the harvest must begin immediately, so the grapes don’t end up being picked by our feathered friends. 

At night, owls reign supreme, perched in the pine and oak trees that adorn the hillsides. The widely spaced rows of vines allow larger animals to roam freely. It’s not unusual for our winegrowers to see a family of wild boars foraging in the early hours of the morning. There are also many burrows. Badgers, moles, field mice: the presence of these nocturnal hunters reflects a living subsoil teeming with insects and vegetation. 

Scattered around the estate are small structures, rustic dwellings built from unhewn stone. According to Louis Wicke, our Vineyard Manager, their hollow spaces provide a natural sanctuary for bats. They thrive happily on the Maison Neuve and Jautan sites, where the winegrowers, as in Aussières, value their nocturnal activity, which proves beneficial in controlling the caterpillar infestation.

In the dark, like the yaca, keep your eyes wide open

Located about 11,000 kilometres from Paradis Casseuil, the Viña Los Vascos estate in Chile’s Colchagua Valley is another idyllic locale. Here, the yaca, a small marsupial with large black eyes that absorb the faintest rays of moonlight to hunt insects at dusk, is cherished. It must remain vigilant while the solitary predator, the culpeo fox, stalks nearby.

Notwithstanding human activity, this viticultural valley preserves its exceptional biodiversity. In a study conducted over an area of less than 7 square hectares in February 2022, at least 23 animal species were documented. (20 species of nocturnal birds were included among them.) 

The Chilean sparrowhawk glides over our vineyards, poised to descend upon its prey. On its rock, our lemniscate lizard is alert. Will it escape the bird of prey? The tension of this scene underscores the delicate balance of our ecosystems. The sparrowhawk kills only to satiate its appetite.

Similar to the hawk, we refrain from overexploiting our soils beyond their capacity.
At all latitudes, we must maintain balance for the benefit of our wines and their surroundings.