Francis Howarth

Bernice Pauahi Bishop Museum · Natural Sciences

The terrestrial arthropod fauna of Rapa Nui has been negatively impacted by human activities, including accidental and purposeful species introductions, which have led to high levels of extinction and extirpation of the native fauna. Unfortunately, the absence of a single, standardized resource documenting all Rapa Nui's native and non-native speci...

A Natural History Survey of North Halawa Valley, O‘ahu, Hawai‘i. 85 pp. Edited by Dan A. Polhemus, Francis G. Howarth, Scott E. Miller

Nothing could possibly live there!" They believed. Indeed, until recently, few specialized cave-adapted animals were known from volcanic, tropical, or oceanic island caves, and plausible theories had been put forward to explain their absence. But assume nothing in science! One must illuminate, explore, and survey habitats before declaring them barr...

This chapter within the book, "Diversity and Speciation of Subterranean Fauna", is now available: https://www.press.jhu.edu/books/title/12872/cave-biodiversity Caves are extraordinary landforms that commonly harbor communities of bizarre animals adapted to live and reproduce only underground. Although biological diversity is relatively low in com...

the lepidopteran fauna of caves remains poorly known largely because of the difficulty in collecting specimens suitable for identification in the physically demanding environment. Here we provide the results of biological surveys spanning more than 40 years in Hawai'i. Lava tube caves are an important landform throughout the islands and especially...

“Nothing could possibly live there!” They said. Indeed, until recently, few specialized cave-adapted animals were known from volcanic, tropical, or oceanic island caves, and plausible theories had been put forward to explain their absence. But assume nothing in science! One must illuminate, explore, and survey habitats before declaring them barren....

Subterranean ecosystems are among the most widespread environments on Earth, yet we still have poor knowledge of their biodiversity. To raise awareness of subterranean ecosystems, the essential services they provide, and their unique conservation challenges, 2021 and 2022 were designated International Years of Caves and Karst. As these ecosystems h...

Brazil’s caves, home to diverse species and minerals, were stripped of protections by a recent presidential decree.

The 15th UN Convention on Biological Diversity (CBD) (COP15) will be held in Kunming, China in October 2021. Historically, CBDs and other multilateral treaties have either alluded to or entirely overlooked the subterranean biome. A multilateral effort to robustly examine, monitor, and incorporate the subterranean biome into future conservation targ...

The 15th UN Convention on Biological Diversity (CBD) (COP15) will be held in Kunming, China in October 2021. Historically, CBDs and other multilateral treaties have either alluded to or entirely overlooked the subterranean biome. A multilateral effort to robustly examine, monitor, and incorporate the subterranean biome into future conservation targ...

The lava tubes at Undara became internationally recognised in the late 1980s, when 24 species of terrestrial cave-adapted invertebrates (troglobionts) were recorded from Bayliss Cave, making it one of the 20 richest known cave communities in the world at the time. Over the last decades, several of the Undara species have been taxonomically describe...

Caves and cave-like voids are common features within and beneath glaciers. The physical environment is harsh and extreme, and often considered barren and devoid of life. However, accumulating evidence indicates that these caves may support a diverse invertebrate fauna with species endemic to each region. As glaciers continue to disappear at an alar...

We review the diversity of moths, Lepidoptera, known from caves in Hawai'i. Twenty-five spp are listed, of which 6 are alien, 3 are natives accidentally in caves; and 16 natives show morphological or behavioral traits to live in caves.

Although there are no published studies and limited data documenting damage by rodents in Hawaiian caves, our incidental observations during more than 40 years of surveying caves indicate that introduced rodents, especially the roof rat, Rattus rattus, pose significant threats to vulnerable cave resources. Caves, with their nearly constant and pred...

Adaptive shift is an evolutionary phenomenon in which individuals from an existing population change to exploit a new habitat or food resource. If successful, the new population may diverge behaviorally, morphologically, and physiologically to become a distinct population or species. The phenomenon is inferred from the many examples of adaptive rad...

An annotated list of 393 adventive terrestrial arthropod species plus three new varieties of known established species, which have been recorded in Hawaii since the Fourth Edition of Bishop Museum's Hawaiian Terrestrial Arthropod Checklist (Nishida 2002), is presented. This compilation includes records of over 362 nonnative arthropod species publis...

Abstract. An annotated list of 393 adventive terrestrial arthropod species plus three new varieties of known established species, which have been recorded in Hawaii since the Fourth Edition of Bishop Museum’s Hawaiian Terrestrial Arthropod Checklist (Nishida 2002), is presented. This compilation includes records of over 362 nonnative arthropod spec...

Ever-increasing human pressures on cave biodiversity have amplified the need for systematic, repeatable, and intensive surveys of cave-dwelling arthropods to formulate evidence-based management decisions. We examined 110 papers (from 1967 to 2018) to: (i) understand how cave-dwelling invertebrates have been sampled; (ii) provide a summary of techni...

Aim: Identify the optimal combination of sampling techniques to maximize the detection of diversity of cave-dwelling arthropods. Location: Central-western New Mexico; northwestern Arizona; Rapa Nui, Chile. Methods: From 26 caves across three geographically distinct areas in the Western Hemisphere, arthropods were sampled using opportunistic col...

Subterranean habitats form wherever erosion or deposition creates an interconnected system of voids. These systems occur in unconsolidated sediments, in karst, volcanoes, sandstone, and granites, and together they represent one of the most extensive ecosystems on Earth. Their extent depends on the degree of connectivity among the voids, allowing fo...

Why certain animals lose features believed essential, like eyes, bodily color, and robustness, to live permanently underground has long intrigued biologists and laymen. Many of these features evolved independently and shared among diverse groups living in caves including both terrestrial and aquatic cavernicoles. The degree of change often correlat...

Two new endemic Hawaiian Lepidoptera species are herein described; both are associated with caves. The new species, Pseudoschrankia nohoana sp. nov. and Mestolobes olali sp. nov., have been found exclusively in caves or cave entrances on the Big Island of Hawai‘i, although neither species appears to possess any specializations for living in caves.

Located over 3800 km from the nearest continent, the Hawaiian Islands have previously been thought to support only one endemic land mammal, the extant Hawaiian hoary bat (Lasiurus cinereus semotus), a taxon that apparently initially dispersed from mainland North America between 10,000 and 7000 years ago. Some uncertainty exists regarding the status...

Hawai‘i is at the Crossroads of the Pacific with material originating from a vast area of the world. Those involved in Hawai‘i, U.S. and world agriculture are keenly interested in learning which pest species are or are not already established in Hawai‘i. To address this need, we compiled a list of terrestrial arthropods that have been discovered in...

Caves are considered buffered environments in terms of their ability to sustain near-constant microclimatic conditions. However, cave entrance environments are expected to respond rapidly to changing conditions on the surface. Our study documents an assemblage of endemic arthropods that have persisted in Rapa Nui caves, despite a catastrophic ecolo...

Caves are considered buffered environments in terms of their ability to sustain near-constant microclimatic conditions. However, cave entrance environments are expected to respond rapidly to changing conditions on the surface. Our study documents an assemblage of endemic arthropods that have persisted in Rapa Nui caves, despite a catastrophic ecolo...

Caves and cavernous rock strata comprise a significant portion of the earth’s surface. These caves and associated interconnected voids often support unique, mysterious ecosystems composed of communities of highly specialized organisms. Bats, birds, and many invertebrates roost in caves and support communities of scavengers and predators. Obligate c...

We provide the first United States records of the Old World biting midge, Forcipomyia (Lepidohelea) pulcherrima SANTOS ABREU (Diptera: Ceratopogonidae), from California, Florida and Hawaii. The fourth instar larva of F. pulcherrima is also described and illustrated for the first time.

The Hawaiian Islands provide the venue of one of nature's grand experiments in evolution. Here, we present morphological, behavioral, genetic, and geologic data from a young subterranean insect lineage in lava tube caves on Hawai'i Island. The Oliarus polyphemus species complex has the potential to become a model for studying rapid speciation by st...

Strongylium cultellatum Mäklin, 1867 New state record (Fig. 1) This Asian species has turned up on o‘ahu but not yet from any of the other Hawaiian islands. Strongylium cultellatum was described from Hong Kong and has been reported extensively from Japan, including the Ryukyu Islands, and Korea. Interestingly, S. cultellatum has also been reported...

Numerous definitions of adaptive radiation have been proposed. Almost all incorporate the idea of diversification in ecological roles, although they differ in their emphasis on relative rates of proliferation. Here, we propose a definition that seeks to be general but at the same time removes any implication of process: adaptive radiation is a patt...

Plant roots are an important component of underground food webs in mesocaverns, lava tubes, and solution caves. Trees such as Metrosideros , Eucalyptus , Ficus , and Brachychiton are adapted to send their roots through porous rock to get water and nutrients. These trees are primary producers, photosynthesizing and sending energy in the form of carb...

As the most isolated group of high islands in the world, the Hawaiian archipelago occupies a very special place in insect conservation: first as a cradle of evolution of a remarkable endemic fauna and second as a prime example of the vulnerability of island environments to anthropogenic changes - especially the effects of alien species. Lessons fro...

Full report available at: http://hbs.bishopmuseum.org/publications/pdf/tr58.pdf

There has been considerable debate on risks associated with biological control, and partly resulting from this, research has addressed a number of questions which have subsequently led to a greater understanding of risk assessment and biosafety. Controversy which arose in the 1980s about the environmental safety of biological control initially crea...

This chapter discusses the subterranean biome, highlighting terrestrial systems and the insects that are obligately adapted to live permanently in underground voids. The most conspicuous aspect displayed by obligate cave arthropods is the reduction of structures normally considered adaptive. Cave species also often lack a circadian rhythm and have...

Although temperate cave-adapted fauna may evolve as a result of climatic change, tropical cave dwellers probably colonize caves through adaptive shifts to exploit new resources. The founding populations may have traits that make colonization of underground spaces even more likely. To investigate the process of cave adaptation and the number of time...

Although temperate cave-adapted fauna may evolve as a result of climatic change, tropical cave dwellers likely colonize caves through adaptive shifts to exploit new resources. The founding populations may have traits that make colonization of underground spaces even more likely. To investigate the process of cave adaptation and the number of times...

P-43 Hawai‘i’s Nemobiinae Crickets: Unique Components of Caves and High-energy Marine Ecosystems Henrietta Croom1 , Shelley James3 , Rodriqo Valasquez Gonzales3 , Fred Stone4 , Anna Karsin5 , Francis Howarth2 1 The University of the South-Sewanee, Sewanee, TN, 2Hawaii Biological Survey, Honolulu, HI, 3Pacific Center for Molecular Biodiversity-Bisho...

Lava tube cave ecosystems on the volcanic islands of Hawai‘i support communities of rare and highly specialized cave arthropods. In these cave ecosystems, plant roots, both living and dead, provide the main energy source for cave animals. Loss of deep-rooted plants over caves will affect populations of cave-adapted animals living below. Furthermore...

We assessed evolutionary relationships among Hawaiian cave-adapted isopods using a maximum-likelihood criterion to analyze cytochrome oxidase I nucleotide sequences. Results support morphological data that two genera of philosciid isopods have invaded caves independently in the islands. In the genus Littorophiloscia, a sister relationship between a...

We report here some factors that affect the relationship between hind femur length (HFL) to crop-empty live weight (CELW) and propose a quantitative, non-lethal measurement ratio that has potential as an index of extent of adaptation to a cavernicolous existence in "crickets". Curvilinear relationships exist between HFL and CELW for camel crickets...

Numerous definitions of adaptive radiation have been proposed. Almost all incorporate the idea of diversification in ecological roles, although they differ in their emphasis on relative rates of proliferation. Here, we propose a definition that seeks to be general but at the same time removes any implication of process: adaptive radiation is a patt...

The introduction of alien, or nonindigenous, animals and plants has been identified by scientists and policy makers as a major threat to biodiversity in marine ecosystems. Although government agencies have struggled to control alien species on land and freshwater for decades with mixed success, the control of alien marine species is in its infancy....

The importation and release of non-indigenous organisms to control pest populations continues to be promoted as environmentally safe; however, accumulating evidence from past and current projects raises serious concerns. Biological control technology using non-indigenous agents is as highly unnatural and anthropocentric as is the use of chemical pe...

Biological control uses three strategies: management practices to enhance native agents already occurring in the system (Chapter 4); captive rearing and release of resident native agents (Chapter 3); and importation and release of non-native agents (sometimes termed ‘classical biological control’) (Chapter 2). A fourth strategy is rapidly being dev...

Although geologically young, the Hawaiian Islands harbour a rich and remarkably diverse fauna of terrestrial troglobites: more than 70 cave species are known from Kauai, Oahu, Molokai, East Maui, and Hawaii Island. Among the more speciosc groups that have invaded the subterranean biome are the planthoppers (Homoptera Cixiidae) of the genus Oliarus....