Spring’s fiery feast: How Bangladesh’s showy blossoms sustain wildlife

In Bangladesh, the arrival of Bashanta Ritu, the spring season, is far more than a change in weather or a burst of colour in the landscape. It is a profound ecological event, quietly orchestrating one of nature's most important seasonal interactions between plants and animals.

From the bustling capital Dhaka to the remote charlands, forest edges, countrysides, and coastal belts, large deciduous trees suddenly ignite the skyline with dazzling shades of crimson, vermilion, and orange.

These are not merely flowers meant to please the human eye, they are biological powerhouses, sustaining a wide spectrum of wildlife during a crucial time of the year.

The fiery trinity of Bangladesh's forests

At the heart of this seasonal spectacle are three iconic native trees: Bombax ceiba (Shimul, Silk Cotton Tree), Butea monosperma (Palash, Flame of the Forest), and Erythrina variegata (Mandar, Coral Tree).

Together, they form what may be called Bangladesh's "spring trinity" of flowering giants. Blooming between February and April, these trees have evolved a remarkable strategy, they shed almost all their leaves before flowering.

This leafless state ensures that their large, brightly coloured blossoms are fully exposed, highly visible, and easily accessible to pollinators from long distances.

Moreover, each species exhibits floral arrangements that have evolved to effectively attract a wide range of pollinators, including bats, primates, squirrels, civets, birds, and insects, to feed on nectar, thereby facilitating cross-fertilization.

Correspondingly, these animals have also undergone adaptive changes, with their mouthparts and beaks specialized for licking or extracting nectar from flowers.

Nature's nectar bowls in the sky

The flowers themselves are masterpieces of evolutionary design. Large, fleshy, waxy, and often cupor boat-shaped, they function like natural containers of nectar, almost like "skyward jars of honey."

Largest of parakeets this Alexandrine Parakeet is eating calyx and hard base of Palash flowers.

Among the trio, Shimul produces the largest blooms, often several inches across, followed by the vivid Palash and the coral-red Mandar. Their thick petals and sturdy structures allow birds and mammals to perch, grip, or probe comfortably while feeding.

The nectar is rich in sugars, providing an immediate and high-energy food source, especially vital at the end of the dry winter when other food sources are limited.

Blooming in waves: A timed ecological gift

One of the most fascinating ecological strategies of these trees lies in their flowering pattern.

Although a tree may remain in bloom for a month or more, individual flowers last only a few days, and not all buds open at once. Instead, flowering occurs in successive waves.

A Jungle Myna drinking nectar from Shimul flower.

This staggered blooming ensures a continuous supply of nectar over weeks, preventing resource depletion and supporting a stable and diverse community of nectar feeders.

It is a finely tuned system that reflects millions of years of co-evolution between plants and their pollinators.

When trees turn into wildlife cafeterias

As these trees come into bloom, they transform into bustling hubs of wildlife activity. In both urban and rural Bangladesh, flowering trees become gathering points for an astonishing variety of birds.

Parakeets—such as the Alexandrine, rose-ringed, and plum-headed—descend in noisy flocks. Mynas, starlings, orioles, drongos, treepies, bulbuls, and sunbirds compete for access to the nectar.

Even species not typically associated with nectar feeding, such as crows and woodpeckers, are often observed visiting these flowers.

The scene is dynamic and vibrant, filled with calls, movements, and interactions.

Where forests come live with nectar

In forested landscapes, the ecological drama becomes even richer.

At places like Satchari National Park, a single flowering Mandar tree can attract an extraordinary diversity of wildlife.

Birdwatchers often gather near such trees to observe rare and migratory species, including barbets, green pigeons, cuckoos, bulbuls, leafbirds, mynas, starlings, finches, sunbirds, flowerpeckers, spiderhunters, and fairy bluebirds.

From monkeys to bats: A 24-hour feast

Mammals too take advantage of this seasonal bounty. Monkeys, particularly langurs and macaques, climb the branches to feed on nectar and petals.

Pyare’s Leaf Monkeys are munching of the coral flowers of the Mandar tree.

Squirrels dart between branches, while civets and fruit bats visit under the cover of night.

The flowers thus support both diurnal and nocturnal communities, extending their ecological influence across the entire daily cycle.

The buzz behind the bloom

In addition to vertebrates, these blooms are magnets for invertebrates. Bees, butterflies, moths, wasps, beetles, and ants swarm the flowers, drawn by the rich nectar and pollen.

These insects play a critical role in pollination, transferring pollen from flower to flower and ensuring successful reproduction.

A Golden-fronted Chloropsis drinking nectar from Mandar flowers.

In many cases, the relationship is mutually beneficial, plants receive pollination services, while insects obtain nourishment.

The abundance of insects, in turn, supports insectivorous birds and other predators, creating cascading effects throughout the food web.

Each tree tells a different ecological story

Each of the three species contributes uniquely to this ecological network.

Shimul, with its towering height and massive flowers, often dominates open landscapes and urban spaces. Its blossoms are particularly important for larger birds and mammals that require sturdy perches.

Palash, smaller in stature but equally striking, is commonly found in both rural and urban areas.

Its flowers are culturally significant and widely used in traditional practices, yet they also serve as a critical food source for pollinators.

Mandar, though less celebrated, plays a vital ecological role. Its flowers produce abundant nectar, and the tree's ability to fix nitrogen enriches soil fertility, supporting surrounding vegetation.

An outsider joins the feast

Interestingly, even non-native species have begun to integrate into this seasonal system.

The introduced Spathodea campanulata (Rudrapalash), brought to the region during the colonial period, produces large, showy flowers rich in nectar.

In urban areas, particularly in botanical gardens and government premises, it often flowers alongside the native species.

In some cases, its blooming period extends beyond that of local trees, sometimes lasting several months or even appearing intermittently throughout the year.

This extended flowering can provide additional nectar resources, although its ecological role compared to native species remains a subject of interest.

Flowers of memory and identity

Beyond their ecological importance, these flowering trees are deeply embedded in the cultural and emotional landscape of Bangladesh.

The fiery blossoms of Palash are closely associated with national identity and are often worn during celebrations such as Ekushey February, the Martyrs Day and the International Mother Language Day.

Shimul trees evoke memories of rural childhoods, village paths, and open fields. Even Mandar, once used as a natural barrier in agricultural fields due to its spiny branches, carries a legacy of practical and ecological utility.

These trees are not just components of the ecosystem, they are part of the memories and seasonal rhythm of the country.

Fading giants: A silent decline

Yet, despite their importance, these species face increasing pressure. Urban expansion, road development, and changes in land use have reduced the number of mature flowering trees, particularly in urban areas.

Old Shimul and Palash trees that once stood as landmarks are gradually disappearing. With them, we risk losing not only aesthetic beauty but also critical ecological functions.

The decline of such nectar sources can have cascading impacts on pollinators, birds, and other wildlife that depend on them.

Planting back the fire of spring

Conserving and planting these species should therefore be a priority in both urban and rural planning.

Incorporating Shimul, Palash, and Mandar into roadside plantations, public parks, school premises, and afforestation programs can help restore ecological balance while enhancing landscape beauty.

Unlike many exotic ornamental species, these native trees are well adapted to local conditions and support far richer biodiversity.

More than beauty: A system that sustains life

In essence, the spring blossoms of Bangladesh represent a remarkable convergence of beauty and function. What appears to us as a fleeting burst of colour is, in reality, a carefully timed ecological phenomenon that sustains life across multiple levels.

These large, showy flowers, laden with nectar, serve as lifelines for countless species, from tiny insects to large mammals. They remind us that in nature, even the most visually striking displays often carry deeper biological significance.

As we admire the reddish-orange blossoms lighting up our skies, it is worth remembering that we are witnessing not just a season, but a vital ecological process, one that deserves both appreciation and protection.

A note from my childhood

I was born and partly raised in Borobari, in the village of Ballia under Dhamrai Upazila, about 45 kilometres from the capital, Dhaka. In our village and surrounding neighbourhoods, all three species of these dazzling flowers were found in abundance.

Toward the end of the flowering season, we would spend busy days gathering silk cotton. Our parents used this cotton to make small, soft pillows for newborn babies.

From the large spines at the base of the shimul tree trunk, we would collect a few, rub them against a concrete wall or a grinding stone, and turn them into makeshift dice for playing Ludo, since we often lost the original ones.

These are the spikes from Shimul tree we used to for the makeshift dice of a Ludo.

Traditionally, the wood of the shimul tree has been used to make packing boxes, matchboxes, and matchsticks, though it is not considered valuable for furniture or fuelwood.

Dried palash leaves were woven into small bowls, which were used for selling grocery items such as traditional Bengali sweets.

The wood was commonly used to make farming tools, as well as items for Sanatan religious ceremonies, including special spoons and oil pots. The flowers themselves were always in demand, for women's adornment and for use in religious rituals.

Mandar branches were traditionally used to build fences and barricades, helping to keep cattle from straying into fields and to deter trespassers.

Even thatched houses often had fences made of mandar branches for the same purpose.