Marine heat waves drive bleaching and necrosis of temperate sponges.

Marine heat waves (MHWs) are extended periods of excessively warm water1 that are increasing in frequency, duration, intensity, and impact, and they likely represent a greater threat to marine ecosystems than the more gradual increases in sea surface temperature.2,3,4 Sponges are major and important components of global benthic marine communities,5,6,7 with earlier studies identifying tropical sponges as potential climate change "winners."8,9,10,11 In contrast, cold-water sponges may be less tolerant to predicted ocean warming and concurrent MHWs. Here, we report how a series of unprecedented MHWs in New Zealand have impacted millions of sponges at a spatial scale far greater than previously reported anywhere in the world. We reported sponge tissue necrosis12 and bleaching (symbiont loss/dysfunction),13 which have been previously associated with temperature stress,6,12,14 for three common sponge species across multiple biogeographical regions, with the severity of impact being correlated with MHW intensity. Given the ecological importance of sponges,15 their loss from these rocky temperate reefs will likely have important ecosystem-level consequences.

Ontogenetic variation in the auditory sensitivity of black sea bass (Centropristis striata) and the implications of anthropogenic sound on behavior and communication.

Black sea bass (Centropristis striata) is an important fish species in both commercial and recreational fisheries of southern New England and the mid-Atlantic Bight. Due to the intense urbanization of these waters, this species is subject to a wide range of anthropogenic noise pollution. Concerns that C. striata are negatively affected by pile driving and construction noise predominate in areas earmarked for energy development. However, as yet, the hearing range of C. striata is unknown, making it hard to evaluate potential risks. This study is a first step in understanding the effects of anthropogenic noise on C. striata by determining the auditory detection bandwidth and thresholds of this species using auditory evoked potentials, creating pressure and acceleration audiograms. These physiological tests were conducted on wild-caught C. striata in three size/age categories. Results showed that juvenile C. striata had the significantly lowest thresholds, with auditory sensitivity decreasing in the larger size classes. Furthermore, C.striata has fairly sensitive sound detection relative to other related species. Preliminary investigations into the mechanisms of their sound detection ability were undertaken with gross dissections and an opportunistic micro-computed tomography image to address the auditory structures including otoliths and swim bladder morphology. Crucially, the auditory detection bandwidth of C. striata, and their most sensitive frequencies, directly overlap with high-amplitude anthropogenic noise pollution such as shipping and underwater construction.