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Emerald ash borer (EAB) has killed millions of ash trees in the United States and Canada, yet impacts on terrestrial-aquatic linkages are largely unknown. Ash tree death along streams creates canopy gaps, increasing light to riparian plants and potentially affecting organic matter subsidies. Six EAB-related canopy gaps along streams across a gradient of timing of EAB invasion in Michigan were characterized for coarse woody material (CWM), terrestrial and aquatic leaf litter and their associated bacterial communities, and macroinvertebrates upstream, downstream, and at the center of the gap. Stream sites downstream of EAB-related canopy gaps had significantly lower dissolved oxygen and macroinvertebrate diversity than sites upstream and at the gaps. Yet there was no difference in CWM or aquatic leaf litter, likely due to downstream movement of organic matter from upstream riparian sources. Low abundance bacterial amplicon sequence variants unique to gap or forest were detected in leaves and leaf litter, suggesting that EAB-related canopy gaps altered leaf-associated bacterial communities. Overall, EAB invasion indirectly impacted some variables, while organic matter dynamics were resistant to change. [ABSTRACT FROM AUTHOR]

This report describes a cold case in which a cadaver of a 28-year-old female was exhumed in February 2005 from a cemetery in Battle Creek, Michigan. She had sustained a gunshot wound to the head and was found dead in her home on November 15, 1977. The body of the victim was subsequently embalmed and then buried at a depth of 1.8 m in an unsealed casket that was placed inside an unsealed cement vault. The exhumation yielded thousands of live specimens of a single species of the order Collembola or spring tails, Sinella ( Coecobrya) tenebricosa (Entomobryidae). This species is considered to be a “tramp” species, cosmopolitan in the United States and Canada. Due to the ideal environmental conditions at the site, the population of this species underwent growth and development inside the casket for a number of years. Collected with the Collembola were large numbers of Acarina (mites) of the Family Glycyphagidae, and fly puparia, Conicera tibialis Schmitz (Order: Diptera, Family: Phoridae), also known as coffin flies. These invertebrates are sometimes mentioned by forensic investigators as occurring on corpses in graves, but aspects of their life history are rarely described. The species of Collembola that was found surviving and reproducing on this corpse in a casket exhumed after 28 years was the oldest reported grave site occurrence for any collembolan species based on a survey of the literature back to 1898. [ABSTRACT FROM AUTHOR]

• Ash trees were a major overstory species of many riparian forests before emerald ash borer. • More than 85% of mature ash have died in sites spanning southern Michigan. • Ash saplings were abundant but seedlings were rare in canopy gaps. • Dense sedge cover has excluded tree seedling establishment. • Invasive plant cover was not higher in canopy gaps than adjacent intact forests. High levels of ash (Fraxinus spp.) mortality have been reported in areas of North America following invasion of emerald ash borer (EAB) (Agrilus planipennis Fairmaire) (Coleoptera: Buprestidae), but little is known about the impacts of EAB in riparian forests, particularly along first order streams. We delineated canopy gaps resulting from EAB-caused ash mortality along four first order streams in each of three distinct watersheds, which represented a temporal gradient of the EAB invasion across southern Michigan. Time lapsed aerial imagery showed canopy gaps were apparent by 2005, 2010, and 2012 in southeast, central and southwest sites, respectively. We assessed overstory trees, regeneration, shrubs, herbaceous plants, coarse woody debris, and photosynthetically active radiation in each canopy gap and in forests surrounding the gap. Canopy gaps were originally dominated by green ash (F. pennsylvanica) and black ash (F. nigra) but more than 85% of ash basal area was killed by EAB across all sites. Live basal area was greater in forests than in gaps, but was similar among all three watersheds. A lower percentage of dead ash trees remained standing and volume of ash coarse woody debris was higher in southeastern sites, with the longest history of EAB invasion, than in central and southwestern sites. Species richness of overstory trees was higher in forests (34 species) than in gaps (27 species). Photosynthetically active radiation, measured 1.5 m above ground, was 55% higher in canopy gaps than in adjacent forests during summer, but was similar during winter. Species composition of pre-EAB forest overstories and current saplings were similar among canopy gaps; overall, 66.3% of saplings were ash. Sapling species in forested areas adjacent to gaps were often dominated by Acer rubrum , while Quercus rubra, Prunus serotina, Acer saccharum and A. rubrum were common in overstories. Seedlings were rare within gaps now dominated by dense mats of sedges (Carex spp.). Although ash has been functionally lost from riparian forest overstories in most of southern Michigan, consistently high sapling densities, combined with reduced EAB densities, could facilitate ash persistence in post-invasion areas. If EAB densities increase, however, recruitment of ash saplings into the overstory will be limited. Continued monitoring will be important to assess the future status of ash and overstory dynamics in of post-EAB riparian forests. [ABSTRACT FROM AUTHOR]

Necrophagous insects play an important role in the decomposition of vertebrate carrion. The documented colonization, development, and succession of blow flies (Diptera: Calliphoridae) and other arthropods on decomposing carcasses make their communities relevant for use in decomposition ecology and forensic investigations. This relevance relies on the local pool of species available to colonize a carcass, but such community level survey data are not always available. The objective of this research was to conduct a baseline survey of adult Calliphoridae communities from urban-rural land use types in the Great Lakes region. To test how adult blow fly distribution varies with changing landscape in Mid-Michigan, sampling with baited jars and hanging traps was implemented over the summer months of June, July, and August 2017. To determine how blow fly communities differed in urban to rural land cover, seven cities were selected with site locations ranging from high intensity developed areas to cultivated crop fields. Over 97,000 individual flies were captured represented by 11 Calliphoridae species. The adult Calliphoridae communities were primarily structured by land use type and month of collection, with these two factors interacting, suggesting that the effect of location varied by time of year. The two most abundant species, Phormia regina (Meigen) and Lucilia sericata (Meigen), cumulatively comprised 88.5% adult flies from Mid-Michigan. These findings provide a baseline database of Great Lakes Calliphoridae, with potential use in forensic research and casework., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The most common application of forensic entomology involves estimating a portion of the postmortem interval (PMI), which usually assumes that blow flies (Diptera: Calliphoridae) do not oviposit nocturnally. Research objectives were to (1) investigate blow fly nocturnal oviposition in relation to sunrise and sunset in Michigan; (2) evaluate abiotic variables postulated to affect blow fly oviposition; and (3) conduct laboratory experiments testing blow fly activity under complete darkness. In 2006, nocturnal oviposition was evaluated in relation to sunset by exposing pigs to fly colonization at 1-h intervals, beginning 2 h before and ending 2 h after sunset. This test was replicated in 2007; however, replicate pigs were placed in the field 2 h after sunset, and hourly observations were made into the following morning. Oviposition was never observed at night. In a laboratory experiment, Lucilia sericata (Meigen), never oviposited on liver hanging above or placed directly on the ground in a completely dark room, Another dark room laboratory study documented that adult flies launched into the air could not fly. This study documents that the probability of nocturnal oviposition on pig carcasses in Michigan was extremely low to nonexistent. These results should be considered when estimating a portion of the PMI in forensic entomological investigations.