for the observed enrichment in TEP. Also, due to their natural positive buoyancy, when not ballasted by other particles sticking to them, TEP ascend through the water column and ultimately end up at the SML . A second possible pathway of TEP from the water column to the SML is by bubble scavenging. Next to rising bubbles, another potential transport mechanism for bacteria from the ULW to the SML could be ascending particles or more specifically TEP. Bacteria readily attach to TEP in the water column. TEP can serve as microbial hotspots and can be used directly as a substrate for bacterial degradation, and as grazing protection for attached bacteria, e.g., by acting as an alternate food source for zooplankton. TEP have also been suggested to serve as light protection for microorganisms in environments with high irradiation. Virioneuston Viruses in the sea surface microlayer, the so-called virioneuston, have recently become of interest to researchers as enigmatic biological entities in the boundary surface layers with potentially important ecological impacts. Given this vast air–water interface sits at the intersection of major air–water exchange processes spanning more than 70% of the global surface area, it is likely to have profound implications for marine biogeochemical cycles, on the microbial loop and gas exchange, as well as the marine food web structure, the global dispersal of airborne viruses originating from the sea surface microlayer, and human health. Viruses are the most abundant biological entities in the water column of the world's oceans. In the free water column, the virioplankton typically outnumbers the bacterioplankton by one order of magnitude reaching typical bulk water concentrations of 107 viruses mL−1. Moreover, they are known as integral parts of global biogeochemical cycles to shape and drive microbial diversity and to structure trophic networks. Like other neuston members, the virioneuston likely originates from the bulk seawater. For instance, in 1977 Baylor et al. postulated adsorption of viruses onto air bubbles as they rise to the surface, or viruses can stick to organic particles also being transported to the SML via bubble scavenging. Within the SML, viruses interacting with the bacterioneuston will probably induce the viral shunt, a phenomenon that is well known for marine pelagic systems. The term viral shunt describes the release of organic carbon and other nutritious compounds from the virus-mediated lysis of host cells, and its addition to the local dissolved organic matter (DOM) pool. The enriched