Multi-year soundscape recordings and automated call detection reveals varied impact of moonlight on calling activity of neotropical forest katydids.

Night-time light can have profound ecological effects, even when the source is natural moonlight. The impacts of light can, however, vary substantially by taxon, habitat and geographical region. We used a custom machine learning model built with the Python package to investigate the effects of moonlight on the calling activity of neotropical forest katydids over multiple years.

Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection.

Early predator detection is a key component of the predator-prey arms race and has driven the evolution of multiple animal hearing systems. Katydids (Insecta) have sophisticated ears, each consisting of paired tympana on each foreleg that receive sound both externally, through the air, and internally via a narrowing ear canal running through the leg from an acoustic spiracle on the thorax. These ears are pressure-time difference receivers capable of sensitive and accurate directional hearing across a wide frequency range.

Hearing sensitivity: An underlying mechanism for niche differentiation in gleaning bats.

Tropical ecosystems are known for high species diversity. Adaptations permitting niche differentiation enable species to coexist. Historically, research focused primarily on morphological and behavioral adaptations for foraging, roosting, and other basic ecological factors.

Predation risks of signalling and searching: bats prefer moving katydids.

Males signalling their attractiveness to females are at risk from predators that exploit mating signals to detect and locate prey. Signalling, however, is not the only risky activity in sexual interactions: mate searching can incur risk as well. Male Neotropical pseudophylline katydids produce both acoustic and vibrational signals (tremulations).

Bats Actively Use Leaves as Specular Reflectors to Detect Acoustically Camouflaged Prey.

Filtering relevant signals from noisy sensory input is a crucial challenge for animals [1, 2]. Many bats are acoustic specialists relying on sound to find prey. They discern salient acoustic signals from irrelevant background masking noise.

Low-cost synchronization of high-speed audio and video recordings in bio-acoustic experiments.

In this paper, we present a method for synchronizing high-speed audio and video recordings of bio-acoustic experiments. By embedding a random signal into the recorded video and audio data, robust synchronization of a diverse set of sensor streams can be performed without the need to keep detailed records. The synchronization can be performed using recording devices without dedicated synchronization inputs.

Environmental conditions limit attractiveness of a complex sexual signal in the túngara frog.

Animals choosing particular display sites often balance sexual and natural selection pressures. Here we assess how physical properties of display sites can alter this balance by influencing signal production and attractiveness of the túngara frog (Physalaemus pustulosus). Males that call from very shallow water bodies (few mm depth) benefit from reduced predation risk, but by manipulating water levels, we show that this comes at a cost of reduced attractiveness to females.

The noseleaf of Rhinolophus formosae focuses the Frequency Modulated (FM) component of the calls.

Bats of the family Rhinolophidae emit their echolocation calls through their nostrils and feature elaborate noseleaves shaping the directionality of the emissions. The calls of these bats consist of a long constant-frequency component preceded and/or followed by short frequency-modulated sweeps. While Rhinolophidae are known for their physiological specializations for processing the constant frequency part of the calls, previous evidence suggests that the noseleaves of these animals are tuned to the frequencies in the frequency modulated components of the calls.

Perception of silent and motionless prey on vegetation by echolocation in the gleaning bat Micronycteris microtis.

Gleaning insectivorous bats that forage by using echolocation within dense forest vegetation face the sensorial challenge of acoustic masking effects. Active perception of silent and motionless prey in acoustically cluttered environments by echolocation alone has thus been regarded impossible. The gleaning insectivorous bat Micronycteris microtis however, forages in dense understory vegetation and preys on insects, including dragonflies, which rest silent and motionless on vegetation.

All you can eat: high performance capacity and plasticity in the common big-eared bat, Micronycteris microtis (Chiroptera: Phyllostomidae).

Ecological specialization and resource partitioning are expected to be particularly high in the species-rich communities of tropical vertebrates, yet many species have broader ecological niches than expected. In Neotropical ecosystems, Neotropical leaf-nosed bats (Phyllostomidae) are one of the most ecologically and functionally diverse vertebrate clades. Resource partitioning in phyllostomids might be achieved through differences in the ability to find and process food.

What noseleaves do for FM bats depends on their degree of sensorial specialization.

Background: Many bats vocalizing through their nose carry a prominent noseleaf that is involved in shaping the emission beam of these animals. To our knowledge, the exact role of these appendages has not been thoroughly investigated as for no single species both the hearing and the emission spatial sensitivities have been obtained. In this paper, we set out to evaluate the complete spatial sensitivity of two species of New World leaf-nosed bats: Micronycteris microtis and Phyllostomus discolor.