## 4 Discussion  
Our results confirmed recent grower accounts of _D. suzukii_ outbreaks in California strawberry fields harvested for both the fresh and processing markets. In their analysis of economic losses attributable to SWD infestation, [PERSON] et al. [15] excluded California fresh strawberries from their projected revenue loss estimates because significant yield loss had not been observed. They attributed the lack of reported infestation in fresh strawberries to management practices (especially insecticides) used for other pests, shorter harvest intervals for fresh relative to processed fruit, and earlier harvest timing for fresh fruit. It seems likely that insecticide resistance to multiple classes reported in California berry crops documented since 2017 could be an important factor in the recent outbreaks. This serves as a caution for growers elsewhere to implement research focusing on SWD resistance management and integrated pest management [16]. In general, our hypothesis that ripe fruit will have higher proportions of SWD was supported in both years, which agreed with findings from previous research. For instance, [PERSON] et al. [17] investigated the oviposition behavior of _D. suzukii_ and five closely-related _Drosophila_ species on ripe and rotten fruit using a two-choice laboratory assay and found that _D. suzukii_ females laid almost all their eggs on ripe fruit, whereas _Drosophila ananassae_ [PERSON], _D. melanogaster_, _Drosophila eugracilis_ [PERSON], and _Drosophila takahashii_ [PERSON] only infested rotten fruit, while _D. biarmipes_, a close relative of _D. suzukii_, showed a mild but not statistically significant preference for rotten fruit. When the choice assay was repeated with sliced ripe fruits with exposed flesh and rotten fruits, they found that _D. biarmipes_ laid approximately equal numbers of eggs on both substrates, while _D. melanogaster_ maintained a strong preference for the rotten fruit. These results suggest that the preference for oviposition on ripe fruit has evolved in the lineage leading to _D. suzukii_[17]. In addition, these authors indicated that _D. suzukii_ is attracted to overripe rotten fruit mostly for feeding, and ripe fruit are mostly selected for oviposition [17], which is also in agreement with findings of [PERSON] et al. and [PERSON] et al. [18; 19]. Lower proportions of SWD emerging from overripe fruit could also be due to competition among larvae of _D. suzukii_ and other _Drosophila_ species, mostly _D. simulans_ in California strawberries, that prefer the overripe fruit for oviposition. There have been several studies of interspecific competition between _Drosophila_ species [20; 21; 22]. One of a few studies that show competition among _Drosophila_ species in the field was conducted by [23], who reported that the Sauternes vineyards in France captured _D. suzukii_ in traps, but they were not present in collected grape samples. Although _D. suzukii_ was known to be the first species to attack ripe grapes in the field, 96.7% and 3.3% of the _Drosophila_ infestation in grapes were identified to be caused by _D. melanogaster_ and _D. simulans_, respectively [23]. One explanation for this could be the interspecific competition between larvae. _Drosophila_ larvae within the same food source compete, leading to increased mortality, decreased growth, and reduced fecundity as density increases [24; 25; 26]. Several studies have shown that interference competition between _D. melanogaster_ and _D. suzukii_ may occur since _D. melanogaster_ larvae have a faster feeding rate compared to _D. suzukii_ larvae and develop faster than _D. suzukii_[20; 22; 27]. [PERSON] et al. [28] also indicated that the presence of _D. melanogaster_ significantly reduced _D. suzukii_ emergence and the potential oviposition of the females in a substrate pre-inoculated with the eggs of the same or the other species in a laboratory choice assay. Another study showed that the number of _D.