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Restoration of channelized streams by returning coarse sediment from stream edges to the wetted channel has become a common practice in Sweden. Yet, restoration activities do not always result in the return of desired biota. This study evaluated a restoration project in the Vindel River in northern Sweden in which practitioners further increased channel complexity of previously restored stream reaches by placing very large boulders (>1 m), trees (>8 m), and salmonid spawning gravel from adjacent upland areas into the channels. One reach restored with basic methods and another with enhanced methods were selected in each of ten different tributaries to the main channel. Geomorphic and hydraulic complexity was enhanced but the chemical composition of riparian soils and the communities of riparian plants and fish did not exhibit any clear responses to the enhanced restoration measures during the first 5 years compared to reaches restored with basic restoration methods. The variation in the collected data was among streams instead of between types of restored reaches. We conclude that restoration is a disturbance in itself, that immigration potential varies across landscapes, and that biotic recovery processes in boreal river systems are slow. We suggest that enhanced restoration has to apply a catchment-scale approach accounting for connectivity and availability of source populations, and that low-intensity monitoring has to be performed over several decades to evaluate restoration outcomes.

Because of their better penetration, smaller targeting proteins may be superior to antibodies for radioimmunotherapy of solid tumors. Therefore, Affibody molecules (6.5 kDa) have a potential for being suitable as targeted moiety for radiolabeled therapeutic proteins. Previous studies have demonstrated that a fusion of an Affibody molecule with an albumin-binding domain (ABD) provides a strong noncovalent binding to albumin in vivo. This strong noncovalent binding can be used for reduction of the renal uptake of the Affibody molecule while maintaining a size smaller than that of an antibody, which is important when using residualizing radionuclide labels conjugated to Affibody molecules. The goal of this study was to design and evaluate a new targeting Affibody - ABD fusion protein with improved biodistribution properties for radionuclide therapy. Methods: A novel Affibody-based construct, Z HER2:2891-ABD035-DOTA (ABY-027), was created by fusion of the reengineered HER2-binding Affibody molecule ZHER2:2891 to the N terminus of the high-affinity ABD035, and a maleimido-derivative of DOTA was conjugated at the C terminus of the construct. Binding and processing of 177Lu-ABY-027 by HER2-expressing cells were evaluated in vitro. Targeting of HER2-expressing SKOV-3 xenografts was evaluated in BALB/C nu/nu mice and compared with targeting of previously reported ABD-(Z HER2:342)2. Results: The binding affinity (dissociation constant) of ABY-027 to HER2 (74 pM) was the same as for the parental Z HER2:2891 (76 pM). ABY-027 was stably labeled with 177Lu and 111In with preserved specific binding to HER2-expressing cells in vitro. In vivo receptor saturation experiments demonstrated that targeting of SKOV-3 xenografts in BALB/C nu/nu mice was HER2-specific. 177Lu-ABY- 027 demonstrated substantially (2- to 3-fold) lower renal and hepatic uptake than previously assessed HER2-specific Affibody-based albumin-binding agents. Tumor uptake of radiolabeled ABY-027 at 48 h after injectio, QC 20131122

Telemetry was used to examine spawning migration of sea trout, Salmo trutta L. (n = 126), in two rivers in northern Sweden. The spawning areas defined by radio-tagged fish differed between the river systems. In the River Vindelaelven, sea trout spawned in the main stem and 80% of tagged individuals returned to areas where hatchery-reared juveniles had been previously stocked. In the River Piteaelven, 74% of tagged sea trout ascended tributaries for spawning. Tagged fish were categorised into three groups of migratory pattern. CART (classification and regression tree) analysis indicated that distance from tagging location to spawning site (Sdist) explained the migratory patterns. Large Sdist separated fish with stepwise upstream migration from those with up- and downstream migrations and one-directional direct migration. Fish tagged early in the season migrated the longest distance to spawning areas. Stocking locations and sex explained the large search behaviour up- and downstream in the rivers. The findings are important for the sustainable management of sea trout in the Gulf of Bothnia.

Wild salmon stocks have declined worldwide (NRC 1996) . In many Baltic Sea riversmost wild populations of Atlantic salmon ( Salmo salar L.) and anadromous trout(sea trout, Salmo trutta L.) have been destroyed, with the remaining stocks foundprimarily in rivers within northern Sweden and Finland. Here they suffer high ratesof fishery exploitation, while hydropower regulation and the re-engineering of riversfor floating timber has led to the loss of spawning and rearing habitat and to a lossof connectivity among habitats (McKinnell 1998) .To remain viable in the face of demographic and environmental stochasticity,salmonid populations require a certain level of abundance, positive growth rates,adequate spatial structure, and access to (connectivity among) habitats of sufficientquantity and quality to express their life history and genetic diversity (McElhanyet al . 2000) . To understand what is limiting their productivity and viability anddevelop conservation actions for these threatened populations, we need informationon both the freshwater and marine phases of the salmon and sea trout life cycles.The Salmon Action Plan (SAP) 1997–2010 was adopted by IBSFC (InternationalBaltic Sea Fishery Commission), and states that by 2010 natural production inBaltic rivers should be >50% of the maximum production potential. To date, maximumnatural production levels have primarily been based on expert knowledge ratherthan empirical estimates (e.g. WGBAST 2008) . The Swedish Government nowrecognises the need for index rivers to obtain reliable estimates of abundance,productivity, population structure, and to collect the information on life-historydiversity needed to manage salmonid stocks.From 2005 to 2008, a pilot study was implemented in the River Sävarån (a small,unregulated forest river in northern Sweden), to monitor the downstream migrationsof salmon and trout, and explore its suitability as an index river. Rotary screwtraps were used to investigate the abundance of smolts a, Monitoring juvenile Atlantic salmon (Salmo salar) and sea trout (Salmo trutta) in the river Sävarån, northern Sweden

The combined model produced a tool for evaluating effects on fish populations from passage through hydro-power turbines at dams. Mean blade-strike mortality was higher for adult Atlantic salmon (Salmo salar) and sea-run brown trout (Salmo trutta) (25.2%-45.3%) than for juveniles (5.3%-9.7%). Based on life cycle modeling, salmon populations in two Swedish rivers responded differently to strategies for mitigating mortality caused by fish striking turbine blades. Although population growth rates increased up to 3% and were relatively similar for both rivers. the relative increase in the number of female salmon escaping above a dam annually after 20 years when both juveniles and adults were protected was greater in the River Pitealven (68%) than in the River Vindelalven (46%) and was approximately four times greater in the River Pitealven (38% vs. 10%) when only adults were protected. These population responses were not predicted by estimates of mortality through turbines. They showed the model could be used to evaluate strategies to conserve fish populations affected by dams located in fish migratory corridors and how postspawn adults contributed to population productivity.

Microsatellite DNA variation was used to assess the outcome of stocking Atlantic salmon Salmo salar and migratory trout Salmo trutta in River Savara, N Sweden. No information on pre-stocking genetic composition of S. salar and S. trutta in River Savara was available. In 2 year-classes of S. salar smolt, microsatellite data indicated that post-stocking genetic composition differed markedly (F_ST = 0.048) from the main donor strain, Byskealven S. salar, and from other Gulf of Bothnia S. salar stocks (F_ST 0.047 and 0.132). The STRUCTURE programme failed to detect any substructuring within Savara salmon. It was concluded that only minor introgression estimated to a proportion of 0.11 (95% CI 0.07-0.16) has occurred in S. salar. Salmo trutta showed overall low differentiation among populations with maximum F_ST of 0.03 making analysis more cumbersome than in S. salar. Still, the Savara S. trutta deviated significantly from potential donor populations, and STRUCTURE software supported that majority of trout in Savara formed a distinct genetic population. Admixture was more extensive in S. trutta and estimated to 0.17 (95% CI 0.10-0.25).

The keystone piscivore northern pike Esox lucius can structure fish communities, and models predicting pike-focused connectivity will be important for management of many waters. We explored the ability of pike to colonize upstream locations and modelled presence-absence in lakes based on landscape features derived from maps. An upstream connectivity model (UC model) was generated using data from 87 lakes. We validated the UC model with retrospective whole-lake experiments involving introductions (n = 49) and extirpations (by rotenone) of pike (n = 96), as well as with the natural distribution of pike in lakes (n = 1365) within 26 drainage basin networks in northern Sweden. The UC model predicted the incidence of pike in lakes with stream-connections with 95.4% accuracy, based mainly on a single variable, S-V5max, that measures the minimum distance found between 5 m elevation intervals (= maximum stream slope) along watercourses from nearest downstream source of potential immigrants. Recolonizations of pike in rotenone lakes generated a near-identical classification tree, as in the UC model. The classification accuracy of pike presence in the external validation procedure ranged from 88.7 to 98.7% between different drainage basins. Predictions of pike absence were not as accurate, due possibly to undetected introductions, but still lead to 86.6% overall accuracy of the external validation. Most lakes lacking pike, but misclassified as having pike based on low S-V5max, were isolated from downstream sources of pike by subsurface stream flow through bouldery areas (SSB). Synthesis and applications. The variable S-V5max provides managers with a tool for revealing the location and severity of natural dispersal barriers to pike (and logically also barriers to other species with equivalent or less dispersal capacity). Because presented models only require map-based information, and have high predictive power, they may have the potential to be of fundamental use in predictin