Here are several examples of birds known for constructing some of the most elaborate nests:

• Bald Eagle - These majestic, powerful raptors build the largest nests of any bird in North America. The nests are reused and added onto for many years by the same bonded pair of adult birds. The nests are massive constructions of sticks, vegetation, and debris, sometimes measuring over 9 feet in diameter and weighing up to a ton. The largest noted Bald Eagle nest was recorded in St. Petersburg, Florida, was 10 feet in diameter and 20 feet tall!

• Montezuma Oropendola - These tropical birds create long, hanging nests from tree branches. Their nests can be up to 6 feet long and are woven from fibers and vines. The colony trees where these birds nest can have dozens of these pendulous nests hanging from them, creating a striking visual.

• Sociable Weaver - These birds build enormous communal nests which may be used by hundreds of birds. The nests are complex structures made of sticks and grass with separated nesting chambers that are lined with soft materials. 

• Hamerkop - This bird’s nest is a massive, domed structure made from sticks kept together with mud, often built in the fork of a tree. The nest can be up to 5 feet across and is roofed with a thick layer of sticks, featuring a single entrance at the underside of the nest.

• Hornbills - Many species of Hornbill, like the Great Hornbill, exhibit a remarkable nesting strategy where the female seals herself inside a tree cavity with mud and fruit pulp, leaving only a slit through which the male feeds her and the chicks. This unique method protects them from predators and environmental elements, showcasing an ingenious approach to nesting security.

These examples illustrate the diverse and sophisticated techniques birds employ in nest building, showcasing their natural ingenuity and adaptability. Each species’ nesting style is perfectly adapted to their environmental needs and breeding behaviors, demonstrating the incredible variety in avian architecture.

Special Infrastructure shout-out to Bowerbirds

Bowerbirds are known for their construction prowess as well, but their work is solely for mating, not nesting. Male birds in the Bowerbird family create structures called "bowers" which are designed for attracting mates. Bowers are constructed around a sapling or a wall of sticks are and decorated with twigs, leaves, and various brightly colored objects they collect like shells, berries, and flowers. The shape and style of the bower vary by species, with some creating avenue-like paths lined with decorations, while others build more hut-like structures.

When we think about urban environments, images of bustling streets, towering skyscrapers, and dense human populations come to mind. Yet amidst this concrete jungle, a surprising array of bird species not only survive but thrive. Adapting to city life involves a fascinating blend of biological resilience and behavioral flexibility, allowing birds to exploit new resources and navigate the challenges of urban spaces.

Among the most iconic urban dwellers is the Peregrine Falcon. Renowned for being the fastest animals on earth—capable of diving at speeds over 200 miles per hour to catch their prey—these cosmopolitan raptors have found a surprising ally in tall buildings and skyscrapers. These structures mimic the high cliff ledges Peregrine Falcons traditionally nest on. Cities also provide an abundant supply of prey such as pigeons and smaller birds. Major cities around the globe, from New York to London, now host thriving populations of these falcons, which have adapted remarkably well to urban life.

Streaming nestcams featuring Peregrine Falcons are abundant due to their frequent use of urban buildings for nesting. Right now is a great time to check out cams like the ones linked below, as the Peregrines are busy raising their fluffy young.

• University of Pittsburgh's Cathedral of Learning Falcon Cam
• The Providence Peregrine Live Stream
• Alcatraz Island Nest Webcam
• Chesapeake Conservancy Peregrine Falcon Cam
• Richmond Falcon Cam
• Indiana Michigan Power Center Falcon Cam
• Rochester Falconcam

Then there are Barn Swallows, who traditionally nest in caves, and in barns and other open structures in rural areas. In cities, these agile fliers have transitioned to nesting under bridges and highway overpasses, using these man-made structures to support their mud-built nests. This adaptation not only provides them with safe nesting sites away from many ground predators, but also places them near water sources where insects—their primary food source—are abundant.

Other bird species that thrive in areas of human development are easy to identify: a big clue is in their name (the name we humans gave to them).  Think about where we can find birds like House Sparrows, House Finches and House Wrens, Barn Owls, Roadside Hawks, and House Martins of the Old World.

City parks and gardens are vital refuges for many bird species. Here, smaller birds like sparrows and finches find not only food in the form of plants and insects but also an assortment of bird feeders filled by enthusiastic bird watchers. These green spaces serve as miniature ecosystems within the urban sprawl, offering shelter and breeding sites. The presence of trees and water features in parks also supports a variety of bird species, from the common robin to the more elusive kingfisher in cities with rivers or ponds.

Birdhouses and nesting platforms are another crucial element that bolsters bird populations in urban settings. Many cities have seen successful implementation of nest box programs that encourage species such as Eastern Bluebirds and Purple Martins to take up residence. These initiatives not only help in bird conservation, increase biodiversity and promote a healthy environment, but also engage the local community in wildlife management and education. Platforms and artificial nests provide safe havens for birds to rear their young away from the prying eyes of predators and the disturbances of city life.

Moreover, urban environments are witnessing innovative approaches to support bird life. For instance, some cities have introduced green roofs, which are covered with vegetation and provide a new habitat for urban birds and other wildlife. These green roofs can reduce the "heat island" effect of cities and offer birds a cooler place to rest and feed. They also help in water retention and provide foraging grounds for insects, thus supporting a small but vital food web for urban bird species.

In adapting to urban environments, birds demonstrate remarkable versatility and resilience. While these adaptations highlight their ability to cope with and exploit new environments, they also underscore the importance of human efforts in supporting urban wildlife. By installing birdhouses, maintaining parks, and initiating conservation programs, we can ensure that our cities remain hospitable to a diverse array of bird species.

It's Infrastructure Week on our blog! The series will dive into the fascinating intersection of urban development and bird conservation and other topics related to infrastructure and birds.  As our cities expand and evolve, so too does the need to consider our feathered friends in our architectural and landscaping decisions. From bridges that serve as nesting grounds to green roofs that offer safe havens, we'll explore how modern infrastructure relates to birds.

Birds brighten our skies with their vibrant colors and melodious songs, but they face numerous dangers as they navigate a world increasingly dominated by human infrastructure. As we expand our cities and networks, we create hazards that pose serious threats to avian populations. Among the most pressing concerns are collisions with glass buildings. Thankfully, innovative solutions and architectural designs are emerging that can mitigate these risks, offering hope for safer skies for our feathered friends.

Glass buildings, with their sleek and modern aesthetics, are a staple of urban architecture. However, they pose a significant hazard to birds. The transparent and reflective properties of glass can deceive birds into thinking they're flying towards open sky or habitat, leading to collisions that are often fatal. Each year, it's estimated that millions of birds die from striking glass surfaces. Cities along major migration flyways can be major zones of bird mortality during the spring and fall. This issue has garnered attention from conservationists, architects, and city planners who are all working towards making buildings safer for our feathered friends.

One of the primary reasons glass buildings are so dangerous to birds is that birds don't perceive glass as a barrier. The reflections of trees, sky, and other natural elements on glass surfaces can create an illusion of continuity in their habitat. When birds try to fly through these illusions, they collide with the hard, unyielding glass. Furthermore, during nighttime, interior lights confuse and attract nocturnal migrants, compounding the risk of collisions.

Addressing this issue, several innovative solutions and architectural adjustments can be implemented to help reduce bird collisions with glass buildings:

• Fritted Glass: This type of glass has patterns etched onto it that are visible to birds but minimally intrusive to human eyes. The patterns can take various forms such as dots, lines, or images that cover enough surface area to alert birds of the barrier ahead.

• Angled Glass: Installing glass at an angle can help reduce reflections of the sky and vegetation, which are often the visual cues that mislead birds. Angled glass reduces the severity of these reflections, making the surface more visible to birds as an obstacle.

• External Screens and Netting: Installing screens or netting in front of glass surfaces can physically prevent birds from colliding with the glass. This method doesn't alter the glass itself but provides a barrier that birds can see and avoid.

• UV-reflective Glass: Birds can see ultraviolet light, which is invisible to humans. Glass treated to reflect ultraviolet light can appear clear to humans but is visible to birds. This technology allows buildings to maintain their transparency for people while being an effective deterrent against bird strikes.

• Decals and Window Films: Placing decals or special films on glass surfaces can make windows visible to birds without significantly affecting the view from inside. These decals are often placed in specific patterns that provide cues to birds that there is a barrier.

• Lighting Reduction: Reducing light pollution, especially during migration seasons, can decrease the number of birds attracted to and disoriented by glass buildings at night. Many cities are adopting guidelines that include turning off building lights or dimming them during critical migration periods.

Community involvement is also crucial. Initiatives like bird conservation programs and educational campaigns can raise awareness about the importance of bird-friendly designs. By supporting policies that require or encourage such measures, the public can play a pivotal role in promoting safer environments for birds.

During this infrastructure week, as we continue to build and innovate, it's vital that we consider our impact on the natural world. With thoughtful design and technological advances, we can create infrastructures that not only serve human needs but also protect our avian companions. Ensuring the safety of birds as they navigate the challenges of modern landscapes is not just an act of conservation; it's a commitment to preserving the beauty and diversity of life on Earth.

Further reading:

• Bird-Friendly Buildings
• Bird Safe Buildings
• Bird-Safe Building Guidelines

When it comes to raising their young, birds exhibit a fascinating array of parenting strategies.

One common myth about bird parenting is that it always requires two parents — one male and one female — to successfully raise their young. While this is true for many bird species, it's not a universal rule. The parenting styles in the avian world are as varied and complex as the birds themselves. The truth is much more nuanced and interesting. Let's explore the myth that two parents are required to raise baby birds.

Paired Chick-Rearing Is Typical

In many bird species, parenting is indeed a dual activity. Take, for example, the familiar American Robin. While the female takes care of incubating the eggs, both are involved in feeding and protecting the fledglings. This shared responsibility ensures that at least one parent is always guarding and nurturing the offspring, increasing their survival chances in the unpredictable wild.

Similarly, some species of penguins are famed for their cooperative parenting. In the strategy of the Emperor Penguin, the male takes the first long shift standing over the eggs through the harshest winter conditions, without eating, while the female goes to sea to feed. Upon her return, roles switch, with the female taking over chick-rearing duties. This level of mutual participation is crucial for survival in their extreme environment.

Sometimes Single Parenting Is the Norm

Despite the prevalence of this model, several bird species challenge the notion that two parents are strictly necessary. In some species, single-parent families are not only common but are the norm. For instance, in the case of the Ruby-throated Hummingbird, females manage the bulk of parenting duties on their own, from brooding to feeding and protection.

In the case of the African Jacana, the female is the dominant and more territorial individual. She mates with multiple males, and it’s these males who incubate the eggs and take care of the chicks solo. This role reversal shows how diverse bird parenting can be.

Some Species Practice Breeding Cooperation

The variability in bird parenting strategies extends even further with communal breeding, where multiple birds share parenting duties, sometimes involving individuals that are not the biological parents of or even biologically related to the young. Species like the Acorn Woodpecker live in large family groups where several females lay eggs in the same nest and the group collectively takes care of all the young. This communal approach can alleviate the burden on any single bird and enhance the survival rates of the nestlings.

In some species of birds, such as the Florida Scrub-Jay, older siblings from previous broods help in feeding and protecting the new chicks of subsequent broods. This behavior not only supports the current breeding pair but also provides valuable parenting experience to the younger birds.

Zero Parenting: Brood Parasitism

Then there are brood parasites like the Brown-headed Cowbird, who lay their eggs in the nests of other bird species. The cowbird chick, once hatched, often pushes out the host's eggs and becomes the sole beneficiary of the unsuspecting foster parents' care. This strategy completely removes the biological parents from the nurturing equation, relying instead on deception for the survival of the offspring.

The reasons behind these varied parenting strategies are complex and influenced by ecological and evolutionary pressures. Factors such as predator density, food availability, and environmental conditions can dictate whether a species evolves to favor single parenting, bi-parental care, or communal breeding.

The Loss of an Adult In Paired Chick-Rearing

In species where two parents are generally involved in raising the chicks, the presence of both ensures optimal care: one can forage for food while the other protects and warms the young. However, should one parent perish, the remaining parent may face increased challenges but not necessarily insurmountable ones. The success of single-parenting in such cases largely depends on factors like the species’ natural behavior, the stage of the nestling period, and the environmental conditions.

For instance, in many songbirds, if the male dies after the chicks have hatched, the female alone might still manage to raise the chicks to fledging. This is possible because the most labor-intensive period requiring both parents, which includes egg incubation and early chick rearing, may have passed. At this stage, the demand is primarily for feeding the rapidly growing chicks. If food is abundant and the threats from predators are minimal, a single mother could potentially manage the workload alone.

In the case of the death of the female, leaving the male to care for the eggs or very young chicks, the scenario might be different. In many bird species, males might not be physiologically equipped to incubate eggs or might not have the behavior programmed for such tasks. 

As demonstrated in the examples above, environmental factors play a significant role in nest survival when one parent is lost. In a habitat where food is plentiful and easily accessible, the surviving parent has a better chance of successfully feeding the chicks and themselves. However, in a scenario where food is scarce or requires significant effort to obtain, the stress and physical demands on the single parent could lead to lower success rates for the nest. And the timing of the parent’s death certainly affects outcomes. 

Some bird species have also shown the capacity to find new mates quickly if their partner dies, thereby restoring the dual care system. This flexibility can greatly enhance the survival prospects of the current brood.

Dual Parenting In Birds Myth: Busted

The myth that all birds require two parents to successfully raise their young does not hold up under scrutiny. The avian world is rich with diverse parenting strategies, each adapted to the specific needs and challenges of different species. This diversity demonstrates the adaptability and complexity of birds, making them endlessly fascinating subjects of study and observation.

In an unprecedented and inspiring leap towards conservation, the American Bird Conservancy, alongside other conservatoin agencies, has embarked on a groundbreaking mission in Hawaii to save several critically endangered Hawaiian honeycreepers from the brink of extinction. The culprits behind the looming threat? Invasive Southern House Mosquitoes carrying avian malaria. The solution? A clever, innovative strategy involving the release of non-biting male mosquitoes engineered to curb the mosquito population and, by extension, the spread of the deadly disease.

Hawaiian honeycreepers, with their vibrant plumage and unique evolutionary history, are more than just birds; they are integral to Hawaii's ecological and cultural tapestry. Once flourishing with over 50 native species, the islands now see a stark reduction to merely 17, each teetering dangerously close to oblivion. The initiative, aptly named Birds, Not Mosquitoes (BNM), marks a significant milestone in conservation efforts, particularly as it coincides with Makahiki o Nā Manu Nahele, or the Year of the Forest Bird, amplifying its significance and urgency.

November 2023 saw the first of these mosquito releases on Maui and Kaua‘i, following extensive study, analysis, and regulatory nods from state and federal bodies. This innovative approach introduces mosquitoes carrying a strain of Wolbachia bacteria, harmless to humans but fatal to mosquito progeny. When these engineered males mate with wild females, the resulting eggs fail to hatch, leading to a gradual but significant decrease in mosquito populations.

This technique, already proven in combating mosquito-borne human diseases globally, promises a ray of hope for Hawaii's feathered natives. Without intervention, climate change's warmer, drier conditions push mosquitoes to higher elevations, directly threatening the survival of species like the Kiwikiu and ‘Ākohekohe on Maui, and ‘Akikiki and ‘Akeke‘e on Kaua‘i. Experts warn that without a drastic reduction in mosquito numbers, these birds could vanish within a decade.

Behind this ambitious project is a broad coalition of state and federal agencies, non-profit organizations, and researchers, all united under the banner of the U.S. Department of Interior's Strategy to Prevent the Extinction of Hawaiian Forest Birds. The initiative not only aims to stabilize and eventually increase native bird populations but also sets the stage for future re-introductions from conservation breeding programs.

Monitoring forms the backbone of this initiative, with teams on Maui and Kaua‘i meticulously tracking mosquito populations with traps, as well as malaria prevalence, and bird population dynamics. This extensive, data-driven approach ensures that the intervention's impact is scientifically measured, paving the way for further releases and an expanded fight against avian malaria.

The commitment of nearly $16 million by the current administration under the Investing in America Agenda underscores the project's importance, signaling a collective determination to protect Hawaii's unique biodiversity. As 2024 unfolds, the partnership eyes continued efforts on Maui, expanded operations on Kaua‘i, and a comprehensive Statewide Environmental Assessment to explore wider applications of this conservation tool.

This pioneering endeavor exemplifies the power of collaboration, innovation, and dedication in the face of seemingly insurmountable conservation challenges. As the Birds, Not Mosquitoes project advances, it stands as a testament to the potential for science and unity to forge a future where Hawaii's skies are once again filled with the vibrant chorus of its native honeycreepers.