Answers to Your Questions About Birds - AMA - Vol 4

Podcast Summary

• Exploring the complexities of bird species identification: Ornithologists use physical differences, behavior, and genetic information to identify and distinguish bird species, leading to ongoing discoveries and updates to the list of known species

  The world of bird biology is full of discovery and complexity. During this episode of The Science of Birds podcast, host Ivan Phillipson answered questions from listeners, many of which explored intriguing aspects of bird species identification. Ornithologists have identified around 10,800 bird species, but the process of defining and distinguishing between species is ongoing. Traditional methods like physical differences and behavior have been joined by genetic information in recent decades, leading to both "splitting" (recognizing new species) and "lumping" (combining previously distinct species). New bird species continue to be discovered, with recent examples coming from remote locations like the Indonesian archipelago. The ongoing work of ornithologists not only expands our knowledge of the natural world but also reflects the curiosity and unique perspectives of bird enthusiasts. If you're curious about bird species and want to contribute questions for future episodes, consider joining the Science of Birds community on Patreon.

• Discovering New Bird Species: Splitting, Lumping, and Vagrancy: 111 new bird species were added to the Clements checklist in 2023, mostly due to taxonomic splits, but some were lost due to lumping. Ornithologists estimate several hundred new species can still be identified through splitting, and the thrill of discovering new species remains.

  New bird species are continually being discovered and added to the global list through the processes of splitting and lumping. For instance, in the most recent update of the Clements checklist in 2023, 111 new bird species were added, which is a significant increase considering there are approximately 11,000 bird species. This increase can be attributed to taxonomic splits, where new species are identified and distinguished from previously recognized ones. However, some species were also lost due to lumping, where previously recognized species were merged into a single one. Despite the ongoing discoveries, the number of new bird species that can be found through traditional exploration and discovery is likely to decrease. Ornithologists estimate that there may still be several hundred new species to be identified through splitting. But the thrill of discovering new species on remote lands or planets, as in the age of discovery or even in the future, remains an exciting prospect. Another intriguing topic related to birds is vagrancy, where birds are found far beyond their normal geographic range. These birds, also known as strays or accidentals, can be a once-in-a-lifetime experience for birders. However, their fate is uncertain, as most of them are unlikely to survive long in unfamiliar habitats with unrecognizable food sources and climates.

• Impact of environmental changes on vagrant birds: Vagrant birds face challenges in unfamiliar habitats, often failing to breed. Phenological mismatch, caused by climate change, can lead to resource scarcity and potential starvation for migratory birds.

  Vagrant birds, those that end up in unfamiliar places due to various reasons, often face a challenging existence. While some may survive for years in their adopted habitats, they usually don't breed due to the rarity of encountering another vagrant of the same species. However, there are exceptions, such as when storms bring large groups of birds to the same location, leading to new colonies. Phenological mismatch, a concept related to the effects of climate change on birds, refers to the misalignment between the availability of resources and a species' demand for them. For instance, migratory birds that rely on specific seasonal resources may arrive too late due to earlier spring temperatures, leading to food scarcity and potential starvation. These are just a few insights from the discussion on vagrant birds and phenological mismatch. Overall, it highlights the impact of environmental changes on wildlife and the importance of adaptation for survival.

• Birds adapting to climate change through temperature cues: Birds like McQueen's bustard adapt to climate change by using temperature instead of photoperiod for migration, helping them keep pace with spring green-up. Birds use vocalizations, such as contact calls, to navigate and stay in touch during migration.

  Many bird species are experiencing phenological mismatches due to climate change, which can lead to starvation and other negative consequences. However, not all birds are equally affected. For instance, McQueen's bustard, a large Asian bird, seems to have adapted to this challenge by using temperature as a cue for migration instead of photoperiod. This allows it to keep pace with the changing timing of spring green-up. Regarding the question about why flocks of birds can be loud or silent during migration, it appears that vocalizations, such as contact calls, help birds keep in touch with each other while flying in a flock. These calls can range from loud honking sounds, as seen in Canada geese, to quieter, simpler sounds. Overall, birds use various cues to navigate their migratory journeys, and understanding these cues can provide valuable insights into how birds adapt to a changing climate.

• Success rate of raising chicks increases with parent age: Older birds have a higher success rate in raising chicks due to mastered skills, lower stress, and disease resistance.

  Older, more experienced birds tend to have a higher success rate in raising chicks to the fledgling stage, as shown in the typical pattern of a graph depicting breeding success and parent age. Younger parents are less successful, and this effect is more pronounced in species with longer average lifespans or more social species. For instance, blue-footed boobies in Mexico have the highest survival rate for young chicks when raised by parents between 6 and 12 years old. Snow petrels, a long-lived seabird breeding in Antarctica, can successfully raise chicks almost every year until they die, but only have one chick at a time. Birds in their prime may have mastered their nesting and foraging skills, have relatively low stress levels, and have the highest level of disease resistance, contributing to their peak performance in raising chicks. However, the reasons for the occasional silent flights of geese remain unknown.

• Parental care and recognition process crucial for young birds survival: Loud traffic noise can hinder parent-offspring communication, affecting chick feeding rates in urban environments, but birds like mourning doves adapt and successfully breed and raise young

  The parental care and recognition process is crucial for the survival of young birds. Short-lived birds, especially those with limited breeding opportunities, may not have the luxury to improve their skills in raising a brood. Social species, such as cooperatively breeding ones, seem to have higher chances of survival for their fledglings due to communal care. However, keeping track of fledglings in urban environments can be challenging for parents due to noise levels, making communication more difficult. Research suggests that loud traffic noise can hinder parent-offspring communication, leading to decreased feeding rates for the chicks. Mourning doves, despite building simple nests, have adapted to their environment and still manage to successfully breed and raise their young. Overall, the intricacies of bird breeding and parental care demonstrate the incredible adaptability and resilience of these creatures.

• Mourning Doves Thrive in Unconventional Nests: Mourning doves adapt to various nesting locations and breed multiple times a year, contributing to their population growth. Birds and worms behaviors are complex and not fully understood, with more research needed to explain why birds don't always take advantage of worms' surface appearances.

  Despite having flimsy and unconventional nests, mourning doves are thriving in their environment due to their ability to breed multiple times in a year and adapt to various nesting locations. On the topic of worms and bird behavior, it seems that while worms may come to the surface during rain to avoid drowning or move more easily, birds do not always take advantage of this apparent food bonanza. The reasons for this are not fully understood and may involve factors such as the worms' own survival needs and the birds' foraging strategies. Further research may be needed to fully understand this phenomenon.

• Birds have superior hearing for detecting frequency changes: Birds like Pacific wrens and Montezuma auropendulas have advanced hearing abilities to distinguish complex sounds and frequencies that humans cannot.

  While birds and humans share similar hearing sensitivity, birds have a more discerning hearing ability when it comes to detecting frequency changes over short time intervals. For example, Pacific wrens can distinguish complex songs with minute differences in frequencies that humans might find jumbled. Regarding the Montezuma auropendulas, they are known for their unusual bubbly noises. These birds, which are large blackbirds with long, pointy bills, make these sounds using their syrinx, a sound-producing organ found in songbirds. The syrinx allows birds to produce complex sounds, often layering two different sounds together. Montezuma auropendulas are thought to use their songs as a means of communication within their colonies, and their unique vocalizations set them apart from other bird species. Magpies, another bird species, are known for their diverse range of sounds. While the exact reason for this is not fully understood, it is believed that their complex vocalizations may serve various purposes, such as communication, territory defense, and mate attraction.

• The Australian Magpie's Varied Vocalizations: The Australian Magpie uses distinct vocalizations for different purposes, including territorial defense, romance, and warning of danger, and can mimic other sounds.

  The Australian magpie is a complex and intelligent bird with a diverse range of vocalizations, each serving a specific purpose. While their most famous call, the caroling song, is used to assert territory and defend against intruders, they also have softer songs for romantic pursuits and alarm calls to warn of danger. Additionally, birds, like humans, can sneeze to clear their respiratory systems of foreign particles. The Australian magpie's repertoire of vocalizations and ability to mimic other sounds is still a subject of fascination and research for ornithologists.

• Birds' Coughs and Identification Differences from Humans: Birds lack a human-like diaphragm for coughing and identifying birds requires focusing on bill size, shape, flight patterns, and vocalizations.

  While birds and humans share some similar reflexes, such as coughing and sneezing, their underlying mechanisms are vastly different due to major anatomical differences. For instance, humans have a diaphragm muscle that contracts forcefully during a cough, but birds do not. Instead, bird coughs sound more like chirping noises. When it comes to identifying birds, such as crows and ravens, size is not the most reliable indicator. Instead, look at the size and shape of their bills, as well as their flight patterns and vocalizations. For example, American crows have shorter bills and tend to fly with frequent flapping, while common ravens have thicker, longer bills and soar more often. Additionally, ravens make croaking sounds instead of the classic "caw caw" of crows. As for amazing birding spots, Southeast Arizona in the US is a top pick due to its diverse habitats and unique bird species, including several that are only found in Mexico and beyond.

• Remarkable birding experiences in Australia, Uganda, Ecuador, and Spain: Listeners can engage with the Science of Birds community through Patreon, contribute questions for future episodes, and enjoy new features like a chat room. The podcast offers bird knowledge and encourages audience interaction.

  Learning from this episode of the Science of Birds podcast is that the host, Ivan Phillipson, has had remarkable birding experiences in several countries, including Australia, Uganda, Ecuador, and Spain. He hopes to return to these places in the future and encourages listeners to become Patreon members to contribute questions for future episodes. The podcast is getting close to reaching 100 episodes, and listeners can engage with the community on Patreon through a new chat feature. New members include Julius the Burbnurb, Steph Stout, and Galadriel. Listeners can also email Ivan with feedback or stories about how they defy societal expectations, like a lovestruck Australian magpie. Show notes and merchandise are available on the Science of Birds website. The podcast aims to provide bird knowledge and encourages interaction from its audience.